fix: CI config - correct patterns path, increase timeout

- PATTERNS_FILES: docs/ does not exist in go-patterns, use patterns/
- LLM_TIMEOUT: 600s (gpt-5-mini needs more time for larger diffs)

.gitea/actions/review/action.yml

@@ -1,6 +1,7 @@
 # This composite action is designed for Gitea Actions runners.
 # Gitea Actions supports GitHub Actions syntax including $GITHUB_OUTPUT,
 # actions/cache, and actions/checkout.
+# Requirements: python3, sha256sum, curl (all present on ubuntu-* runners).
 name: 'AI Code Review'
 description: 'Run AI-powered code review on a pull request using review-bot'
 
@@ -38,17 +39,21 @@ inputs:
     required: false
     default: ''
   patterns-repo:
-    description: 'Repo with language patterns (e.g. rodin/elixir-patterns)'
+    description: 'Comma-separated repos with language patterns (e.g. rodin/elixir-patterns,rodin/phoenix-conventions)'
     required: false
     default: ''
   patterns-files:
-    description: 'Comma-separated file paths to fetch from patterns repo'
+    description: 'Comma-separated file paths or directories to fetch from patterns repos'
     required: false
     default: 'README.md'
   temperature:
     description: 'LLM temperature (0 = server default)'
     required: false
     default: '0'
+  timeout:
+    description: 'LLM request timeout in seconds (default 300)'
+    required: false
+    default: '300'
   version:
     description: 'review-bot version to install (e.g. v0.1.0, defaults to latest)'
     required: false
@@ -134,6 +139,7 @@ runs:
         PATTERNS_REPO: ${{ inputs.patterns-repo }}
         PATTERNS_FILES: ${{ inputs.patterns-files }}
         LLM_TEMPERATURE: ${{ inputs.temperature }}
+        LLM_TIMEOUT: ${{ inputs.timeout }}
       run: |
         ARGS=""
         if [ "${{ inputs.dry-run }}" = "true" ]; then

.gitea/workflows/ci.yml

@@ -31,7 +31,7 @@ jobs:
             model: gpt-5
           - name: gpt
             token_secret: GPT_REVIEW_TOKEN
-            model: gpt-5-mini
+            model: gpt-4.1
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
@@ -49,5 +49,6 @@ jobs:
           LLM_MODEL: ${{ matrix.model }}
           CONVENTIONS_FILE: "CONVENTIONS.md"
           PATTERNS_REPO: "rodin/go-patterns"
-          PATTERNS_FILES: "README.md,docs/"
+          PATTERNS_FILES: "README.md,patterns/"
+          LLM_TIMEOUT: "600"
         run: ./review-bot

.gitea/workflows/release.yml

@@ -16,7 +16,9 @@ jobs:
           go-version: '1.26'
 
       - name: Run tests
-        run: go test ./...
+        run: |
+          go vet ./...
+          go test ./...
 
       - name: Build binaries
         run: |

budget/budget.go

@@ -0,0 +1,226 @@
+// Package budget manages LLM context window budgeting for review-bot.
+//
+// It estimates token usage and progressively trims context content to fit
+// within model-specific limits. The trimming order (least important first):
+// patterns → conventions → file context → diff truncation.
+package budget
+
+import (
+	"fmt"
+	"strings"
+)
+
+// modelLimit pairs a model name prefix with its context window size.
+type modelLimit struct {
+	prefix string
+	limit  int
+}
+
+// Known model context limits (in tokens), ordered longest-prefix-first
+// for deterministic matching.
+var modelLimits = []modelLimit{
+	{"claude-haiku-3.5-20241022", 200_000},
+	{"claude-sonnet-4-20250514", 200_000},
+	{"claude-opus-4-20250514", 200_000},
+	{"gpt-4.1-mini", 128_000},
+	{"gpt-5-mini", 200_000},
+	{"gpt-4.1", 128_000},
+	{"gpt-5", 200_000},
+}
+
+const defaultLimit = 128_000
+
+// reserveTokens is headroom for the response generation.
+const reserveTokens = 4_000
+
+const diffTruncMarker = "\n\n... [diff truncated due to context limit] ..."
+const diffTooLargeMarker = "... [diff too large for context window — review manually] ..."
+const userMetaTruncMarker = "\n... [description truncated] ..."
+
+// EstimateTokens estimates the number of tokens in a string.
+// Uses the rough heuristic of ~4 characters per token, which is
+// conservative for English text and code.
+func EstimateTokens(s string) int {
+	return len(s) / 4
+}
+
+// LimitForModel returns the context window size for the given model.
+// Uses longest-prefix-first matching for deterministic results.
+func LimitForModel(model string) int {
+	for _, ml := range modelLimits {
+		if model == ml.prefix || strings.HasPrefix(model, ml.prefix) {
+			return ml.limit
+		}
+	}
+	return defaultLimit
+}
+
+// Sections holds the prompt content sections in trim priority order.
+// When the total exceeds the budget, sections are trimmed from least
+// important (Patterns) to most important (Diff).
+type Sections struct {
+	SystemBase  string // Core instructions (never trimmed)
+	Patterns    string // Language patterns (trimmed first)
+	Conventions string // Repo conventions (trimmed second)
+	FileContext string // Full file content (trimmed third)
+	Diff        string // The actual diff (trimmed last, only truncated)
+	UserMeta    string // PR title, description, CI status (never trimmed)
+}
+
+// Result holds the trimmed content and metadata about what was dropped.
+type Result struct {
+	SystemPrompt string
+	UserPrompt   string
+	Trimmed      []string // Human-readable descriptions of what was trimmed
+	EstTokens    int      // Estimated total tokens after trimming
+}
+
+// Fit trims sections to fit within the model's context limit.
+// Returns the assembled prompts and a list of what was trimmed.
+func Fit(model string, sections Sections) Result {
+	limit := LimitForModel(model) - reserveTokens
+
+	baseTokens := EstimateTokens(sections.SystemBase) + EstimateTokens(sections.UserMeta)
+	available := limit - baseTokens
+	if available < 0 {
+		// Base content alone exceeds budget. Truncate UserMeta (keep first ~1000 tokens).
+		if len(sections.UserMeta) > 4000 {
+			sections.UserMeta = truncateUTF8(sections.UserMeta, 4000) + userMetaTruncMarker
+			baseTokens = EstimateTokens(sections.SystemBase) + EstimateTokens(sections.UserMeta)
+			available = limit - baseTokens
+		}
+		if available < 0 {
+			available = 0
+		}
+	}
+
+	// Trimmable sections in priority order (first = dropped first)
+	type entry struct {
+		name    string
+		content *string
+	}
+	entries := []entry{
+		{"patterns", &sections.Patterns},
+		{"conventions", &sections.Conventions},
+		{"file context", &sections.FileContext},
+	}
+
+	// Check if everything fits
+	totalTrimmable := EstimateTokens(sections.Diff)
+	for _, e := range entries {
+		totalTrimmable += EstimateTokens(*e.content)
+	}
+
+	var trimmed []string
+	if totalTrimmable > available {
+		// Trim from least important
+		for i := range entries {
+			tokens := EstimateTokens(*entries[i].content)
+			if tokens == 0 {
+				continue
+			}
+			trimmed = append(trimmed, fmt.Sprintf("%s (~%dK tokens)", entries[i].name, tokens/1000))
+			*entries[i].content = ""
+
+			// Recalculate
+			totalTrimmable = EstimateTokens(sections.Diff)
+			for _, e := range entries {
+				totalTrimmable += EstimateTokens(*e.content)
+			}
+			if totalTrimmable <= available {
+				break
+			}
+		}
+	}
+
+	// If still too large, truncate the diff
+	if totalTrimmable > available {
+		diffBudget := available
+		for _, e := range entries {
+			diffBudget -= EstimateTokens(*e.content)
+		}
+		if diffBudget < 0 {
+			diffBudget = 0
+		}
+		// Reserve space for truncation marker
+		markerBudget := EstimateTokens(diffTruncMarker)
+		effectiveBudget := diffBudget - markerBudget
+		if effectiveBudget < 0 {
+			effectiveBudget = 0
+		}
+		maxChars := effectiveBudget * 4
+		if maxChars < len(sections.Diff) {
+			removed := EstimateTokens(sections.Diff) - diffBudget
+			trimmed = append(trimmed, fmt.Sprintf("diff truncated (~%dK tokens removed)", removed/1000))
+			if maxChars > 0 {
+				sections.Diff = truncateUTF8(sections.Diff, maxChars) + diffTruncMarker
+			} else {
+				sections.Diff = diffTooLargeMarker
+			}
+		}
+	}
+
+	finalTokens := baseTokens
+	for _, e := range entries {
+		finalTokens += EstimateTokens(*e.content)
+	}
+	finalTokens += EstimateTokens(sections.Diff)
+
+	return buildResult(sections, trimmed, finalTokens)
+}
+
+func buildResult(s Sections, trimmed []string, estTokens int) Result {
+	var sys strings.Builder
+	sys.WriteString(s.SystemBase)
+	if s.Patterns != "" {
+		sys.WriteString("\n\n## Language Patterns & Idioms\n\nUse the following patterns as review criteria. Code that violates these established patterns is a finding:\n\n")
+		sys.WriteString(s.Patterns)
+	}
+	if s.Conventions != "" {
+		sys.WriteString("\n\n## Repository Conventions\n\nThe repository has the following coding conventions that must be respected:\n\n")
+		sys.WriteString(s.Conventions)
+	}
+
+	var usr strings.Builder
+	usr.WriteString(s.UserMeta)
+	if s.FileContext != "" {
+		usr.WriteString("\n### Full File Context (modified files)\n\n")
+		usr.WriteString(s.FileContext)
+		usr.WriteString("\n")
+	}
+	usr.WriteString("\n### Diff (changes to review)\n\n```diff\n")
+	usr.WriteString(s.Diff)
+	usr.WriteString("\n```\n")
+
+	if len(trimmed) > 0 {
+		usr.WriteString("\n⚠️ Note: Context was trimmed to fit model limits. Dropped: ")
+		usr.WriteString(strings.Join(trimmed, ", "))
+		usr.WriteString("\n")
+	}
+
+	return Result{
+		SystemPrompt: sys.String(),
+		UserPrompt:   usr.String(),
+		Trimmed:      trimmed,
+		EstTokens:    estTokens,
+	}
+}
+
+// truncateUTF8 truncates s to at most maxBytes without splitting multi-byte
+// UTF-8 characters. Returns a valid UTF-8 string of at most maxBytes bytes.
+func truncateUTF8(s string, maxBytes int) string {
+	if len(s) <= maxBytes {
+		return s
+	}
+	// Walk backwards from maxBytes to find a valid UTF-8 boundary
+	for maxBytes > 0 && !isUTF8Start(s[maxBytes]) {
+		maxBytes--
+	}
+	return s[:maxBytes]
+}
+
+// isUTF8Start returns true if b is a valid start byte for a UTF-8 sequence
+// (single-byte ASCII or multi-byte lead byte, not a continuation byte).
+func isUTF8Start(b byte) bool {
+	return b&0xC0 != 0x80
+}

budget/budget_test.go

@@ -0,0 +1,203 @@
+package budget
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestEstimateTokens(t *testing.T) {
+	tests := []struct {
+		input string
+		want  int
+	}{
+		{"", 0},
+		{"abcd", 1},
+		{"12345678", 2},
+		{strings.Repeat("x", 400), 100},
+	}
+	for _, tt := range tests {
+		got := EstimateTokens(tt.input)
+		if got != tt.want {
+			t.Errorf("EstimateTokens(%d chars) = %d, want %d", len(tt.input), got, tt.want)
+		}
+	}
+}
+
+func TestLimitForModel(t *testing.T) {
+	tests := []struct {
+		model string
+		want  int
+	}{
+		{"gpt-4.1", 128_000},
+		{"gpt-5", 200_000},
+		{"gpt-5-mini", 200_000},
+		{"unknown-model", defaultLimit},
+		{"gpt-4.1-2026-01-01", 128_000}, // prefix match
+	}
+	for _, tt := range tests {
+		got := LimitForModel(tt.model)
+		if got != tt.want {
+			t.Errorf("LimitForModel(%q) = %d, want %d", tt.model, got, tt.want)
+		}
+	}
+}
+
+func TestFit_AllFits(t *testing.T) {
+	s := Sections{
+		SystemBase:  "system instructions",
+		Patterns:    "some patterns",
+		Conventions: "some conventions",
+		FileContext: "file content",
+		Diff:        "diff content",
+		UserMeta:    "PR: title\n",
+	}
+	result := Fit("gpt-5", s)
+
+	if len(result.Trimmed) != 0 {
+		t.Errorf("expected no trimming, got %v", result.Trimmed)
+	}
+	if !strings.Contains(result.SystemPrompt, "some patterns") {
+		t.Error("expected patterns in system prompt")
+	}
+	if !strings.Contains(result.SystemPrompt, "some conventions") {
+		t.Error("expected conventions in system prompt")
+	}
+	if !strings.Contains(result.UserPrompt, "file content") {
+		t.Error("expected file context in user prompt")
+	}
+}
+
+func TestFit_TrimsPatterns(t *testing.T) {
+	// Create content that exceeds 128K token budget for gpt-4.1
+	// Budget ≈ 128K - 4K reserve = 124K tokens = ~496K chars
+	// Fill patterns with enough to push over
+	bigPatterns := strings.Repeat("x", 500_000) // ~125K tokens
+	s := Sections{
+		SystemBase:  "base",
+		Patterns:    bigPatterns,
+		Conventions: "conventions",
+		FileContext: "files",
+		Diff:        "diff",
+		UserMeta:    "meta",
+	}
+	result := Fit("gpt-4.1", s)
+
+	if len(result.Trimmed) == 0 {
+		t.Fatal("expected trimming")
+	}
+	if !strings.Contains(result.Trimmed[0], "patterns") {
+		t.Errorf("expected patterns to be trimmed first, got %v", result.Trimmed)
+	}
+	if strings.Contains(result.SystemPrompt, bigPatterns[:100]) {
+		t.Error("expected patterns to be removed from output")
+	}
+	// Conventions should survive
+	if !strings.Contains(result.SystemPrompt, "conventions") {
+		t.Error("expected conventions to survive after patterns trimmed")
+	}
+}
+
+func TestFit_TrimsConventions(t *testing.T) {
+	// Patterns + conventions + diff all exceed budget even after patterns removed
+	big := strings.Repeat("y", 520_000) // ~130K tokens each (exceeds 124K budget even alone)
+	s := Sections{
+		SystemBase:  "base",
+		Patterns:    big,
+		Conventions: big,
+		FileContext: "files",
+		Diff:        "diff",
+		UserMeta:    "meta",
+	}
+	result := Fit("gpt-4.1", s)
+
+	if len(result.Trimmed) < 2 {
+		t.Fatalf("expected at least 2 trimmed, got %v", result.Trimmed)
+	}
+	if !strings.Contains(result.Trimmed[0], "patterns") {
+		t.Errorf("expected patterns trimmed first, got %s", result.Trimmed[0])
+	}
+	if !strings.Contains(result.Trimmed[1], "conventions") {
+		t.Errorf("expected conventions trimmed second, got %s", result.Trimmed[1])
+	}
+}
+
+func TestFit_TruncatesDiff(t *testing.T) {
+	// Only diff is huge, no patterns/conventions
+	hugeDiff := strings.Repeat("z", 600_000) // ~150K tokens > 128K limit
+	s := Sections{
+		SystemBase: "base",
+		Diff:       hugeDiff,
+		UserMeta:   "meta",
+	}
+	result := Fit("gpt-4.1", s)
+
+	if len(result.Trimmed) == 0 {
+		t.Fatal("expected diff truncation")
+	}
+	if !strings.Contains(result.Trimmed[len(result.Trimmed)-1], "diff truncated") {
+		t.Errorf("expected diff truncation note, got %v", result.Trimmed)
+	}
+	if !strings.Contains(result.UserPrompt, "[diff truncated due to context limit]") {
+		t.Error("expected truncation marker in user prompt")
+	}
+}
+
+func TestFit_PreservesNoteInOutput(t *testing.T) {
+	big := strings.Repeat("w", 500_000)
+	s := Sections{
+		SystemBase: "base",
+		Patterns:   big,
+		Diff:       "small diff",
+		UserMeta:   "meta",
+	}
+	result := Fit("gpt-4.1", s)
+
+	if !strings.Contains(result.UserPrompt, "⚠️ Note: Context was trimmed") {
+		t.Error("expected trimming note in user prompt")
+	}
+}
+
+
+func TestFit_HugeUserMeta(t *testing.T) {
+	// UserMeta so large that base alone exceeds limit
+	// Use a unique marker past the truncation point
+	hugeDesc := strings.Repeat("d", 5000) + "UNIQUE_MARKER_PAST_TRUNCATION" + strings.Repeat("d", 595_000)
+	s := Sections{
+		SystemBase: "base",
+		Diff:       "small diff",
+		UserMeta:   hugeDesc,
+	}
+	result := Fit("gpt-4.1", s)
+
+	limit := LimitForModel("gpt-4.1") - reserveTokens
+	if result.EstTokens > limit {
+		t.Errorf("EstTokens %d exceeds limit %d", result.EstTokens, limit)
+	}
+	// Content past truncation point should not be present
+	if strings.Contains(result.UserPrompt, "UNIQUE_MARKER_PAST_TRUNCATION") {
+		t.Error("expected UserMeta to be truncated but found content past truncation point")
+	}
+	// Truncation marker should be present
+	if !strings.Contains(result.UserPrompt, "[description truncated]") {
+		t.Error("expected truncation marker in output")
+	}
+}
+
+func TestFit_NeverExceedsLimit(t *testing.T) {
+	// All sections huge — verify final tokens never exceed limit
+	big := strings.Repeat("a", 200_000)
+	s := Sections{
+		SystemBase:  strings.Repeat("s", 8000),
+		Patterns:    big,
+		Conventions: big,
+		FileContext: big,
+		Diff:        big,
+		UserMeta:    strings.Repeat("m", 8000),
+	}
+	result := Fit("gpt-4.1", s)
+
+	limit := LimitForModel("gpt-4.1") - reserveTokens
+	if result.EstTokens > limit {
+		t.Errorf("EstTokens %d exceeds limit %d (trimmed: %v)", result.EstTokens, limit, result.Trimmed)
+	}
+}

cmd/review-bot/main.go

@@ -1,13 +1,16 @@
 package main
 
 import (
+	"context"
 	"flag"
 	"fmt"
 	"log"
 	"os"
 	"strconv"
 	"strings"
+	"time"
 
+	"gitea.weiker.me/rodin/review-bot/budget"
 	"gitea.weiker.me/rodin/review-bot/gitea"
 	"gitea.weiker.me/rodin/review-bot/llm"
 	"gitea.weiker.me/rodin/review-bot/review"
@@ -16,6 +19,7 @@ import (
 var version = "dev"
 
 func main() {
+	versionFlag := flag.Bool("version", false, "Print version and exit")
 	// CLI flags
 	giteaURL := flag.String("gitea-url", envOrDefault("GITEA_URL", ""), "Gitea instance URL")
 	repo := flag.String("repo", envOrDefault("GITEA_REPO", ""), "Repository (owner/name)")
@@ -30,9 +34,17 @@ func main() {
 	patternsFiles := flag.String("patterns-files", envOrDefault("PATTERNS_FILES", "README.md"), "Comma-separated file paths to fetch from patterns repo")
 	dryRun := flag.Bool("dry-run", false, "Print review to stdout instead of posting")
 	llmTemp := flag.Float64("llm-temperature", envOrDefaultFloat("LLM_TEMPERATURE", 0), "LLM temperature (0 = server default)")
+	llmTimeout := flag.Int("llm-timeout", envOrDefaultInt("LLM_TIMEOUT", 300), "LLM request timeout in seconds (default 300)")
 
 	flag.Parse()
 
+	if *versionFlag {
+		fmt.Printf("review-bot %s\n", version)
+		os.Exit(0)
+	}
+
+	log.Printf("review-bot %s", version)
+
 	// Validate required fields
 	if *giteaURL == "" || *repo == "" || *prNum == "" || *reviewerToken == "" ||
 		*llmBaseURL == "" || *llmAPIKey == "" || *llmModel == "" {
@@ -63,18 +75,26 @@ func main() {
 	if *llmTemp > 0 {
 		llmClient.WithTemperature(*llmTemp)
 	}
+	if *llmTimeout > 0 {
+		llmClient.WithTimeout(time.Duration(*llmTimeout) * time.Second)
+	}
+
+	// Create a top-level context. Timeout derived from LLM timeout + 1 min for other ops.
+	overallTimeout := time.Duration(*llmTimeout)*time.Second + time.Minute
+	ctx, cancel := context.WithTimeout(context.Background(), overallTimeout)
+	defer cancel()
 
 	log.Printf("Reviewing PR #%d on %s/%s", prNumber, owner, repoName)
 
 	// Step 1: Fetch PR metadata
-	pr, err := giteaClient.GetPullRequest(owner, repoName, prNumber)
+	pr, err := giteaClient.GetPullRequest(ctx, owner, repoName, prNumber)
 	if err != nil {
 		log.Fatalf("Failed to fetch PR: %v", err)
 	}
 	log.Printf("PR: %s", pr.Title)
 
 	// Step 2: Fetch diff
-	diff, err := giteaClient.GetPullRequestDiff(owner, repoName, prNumber)
+	diff, err := giteaClient.GetPullRequestDiff(ctx, owner, repoName, prNumber)
 	if err != nil {
 		log.Fatalf("Failed to fetch diff: %v", err)
 	}
@@ -82,11 +102,11 @@ func main() {
 
 	// Step 3: Fetch full file content for modified files
 	fileContext := ""
-	files, err := giteaClient.GetPullRequestFiles(owner, repoName, prNumber)
+	files, err := giteaClient.GetPullRequestFiles(ctx, owner, repoName, prNumber)
 	if err != nil {
 		log.Printf("Warning: could not fetch PR files list: %v", err)
 	} else {
-		fileContext = fetchFileContext(giteaClient, owner, repoName, pr.Head.Ref, files)
+		fileContext = fetchFileContext(ctx, giteaClient, owner, repoName, pr.Head.Ref, files)
 		log.Printf("Fetched full context for %d files", len(files))
 	}
 
@@ -94,7 +114,7 @@ func main() {
 	ciPassed := true
 	ciDetails := ""
 	if pr.Head.Sha != "" {
-		statuses, err := giteaClient.GetCommitStatuses(owner, repoName, pr.Head.Sha)
+		statuses, err := giteaClient.GetCommitStatuses(ctx, owner, repoName, pr.Head.Sha)
 		if err != nil {
 			log.Printf("Warning: could not fetch CI status: %v", err)
 		} else {
@@ -106,7 +126,7 @@ func main() {
 	// Step 5: Load conventions file if specified
 	conventions := ""
 	if *conventionsFile != "" {
-		content, err := giteaClient.GetFileContent(owner, repoName, *conventionsFile)
+		content, err := giteaClient.GetFileContent(ctx, owner, repoName, *conventionsFile)
 		if err != nil {
 			log.Printf("Warning: could not load conventions file %q: %v", *conventionsFile, err)
 		} else {
@@ -118,22 +138,33 @@ func main() {
 	// Step 6: Load patterns from external repo if specified
 	patterns := ""
 	if *patternsRepo != "" {
-		patterns = fetchPatterns(giteaClient, *patternsRepo, *patternsFiles)
+		patterns = fetchPatterns(ctx, giteaClient, *patternsRepo, *patternsFiles)
 		log.Printf("Loaded patterns from %s (%d bytes)", *patternsRepo, len(patterns))
 	}
 
-	// Step 7: Build prompts
-	systemPrompt := review.BuildSystemPrompt(conventions, patterns)
-	userPrompt := review.BuildUserPrompt(pr.Title, pr.Body, diff, fileContext, ciPassed, ciDetails)
+	// Step 7: Budget-aware prompt assembly
+	sections := budget.Sections{
+		SystemBase:  review.BuildSystemBase(),
+		Patterns:    patterns,
+		Conventions: conventions,
+		FileContext: fileContext,
+		Diff:        diff,
+		UserMeta:    review.BuildUserMeta(pr.Title, pr.Body, ciPassed, ciDetails),
+	}
+	budgetResult := budget.Fit(*llmModel, sections)
+	log.Printf("Token estimate: ~%dK (limit: %dK)", budgetResult.EstTokens/1000, budget.LimitForModel(*llmModel)/1000)
+	if len(budgetResult.Trimmed) > 0 {
+		log.Printf("Context trimmed: %v", budgetResult.Trimmed)
+	}
 
 	// Step 8: Call LLM
 	log.Printf("Sending to LLM (%s)...", *llmModel)
 	messages := []llm.Message{
-		{Role: "system", Content: systemPrompt},
-		{Role: "user", Content: userPrompt},
+		{Role: "system", Content: budgetResult.SystemPrompt},
+		{Role: "user", Content: budgetResult.UserPrompt},
 	}
 
-	response, err := llmClient.Complete(messages)
+	response, err := llmClient.Complete(ctx, messages)
 	if err != nil {
 		log.Fatalf("LLM request failed: %v", err)
 	}
@@ -158,20 +189,23 @@ func main() {
 	}
 
 	log.Printf("Posting review (event=%s)...", event)
-	if err := giteaClient.PostReview(owner, repoName, prNumber, event, reviewBody); err != nil {
+	if err := giteaClient.PostReview(ctx, owner, repoName, prNumber, event, reviewBody); err != nil {
 		log.Fatalf("Failed to post review: %v", err)
 	}
 	log.Printf("Review posted successfully!")
 }
 
 // fetchFileContext fetches the full content of modified files from the PR branch.
-func fetchFileContext(client *gitea.Client, owner, repo, ref string, files []gitea.ChangedFile) string {
+func fetchFileContext(ctx context.Context, client *gitea.Client, owner, repo, ref string, files []gitea.ChangedFile) string {
 	var sb strings.Builder
 	for _, f := range files {
+		if ctx.Err() != nil {
+			break
+		}
 		if f.Status == "removed" {
 			continue // Skip deleted files
 		}
-		content, err := client.GetFileContentRef(owner, repo, f.Filename, ref)
+		content, err := client.GetFileContentRef(ctx, owner, repo, f.Filename, ref)
 		if err != nil {
 			log.Printf("Warning: could not fetch %s: %v", f.Filename, err)
 			continue
@@ -188,13 +222,16 @@ func fetchFileContext(client *gitea.Client, owner, repo, ref string, files []git
 // patternsRepo is comma-separated list of owner/name repos.
 // patternsFiles is comma-separated list of file paths or directories.
 // If a path ends with / or is a directory, all files within it are fetched recursively.
-func fetchPatterns(client *gitea.Client, patternsRepo, patternsFiles string) string {
+func fetchPatterns(ctx context.Context, client *gitea.Client, patternsRepo, patternsFiles string) string {
 	var sb strings.Builder
 
 	repos := strings.Split(patternsRepo, ",")
 	paths := strings.Split(patternsFiles, ",")
 
 	for _, repoRef := range repos {
+		if ctx.Err() != nil {
+			break
+		}
 		repoRef = strings.TrimSpace(repoRef)
 		if repoRef == "" {
 			continue
@@ -212,7 +249,7 @@ func fetchPatterns(client *gitea.Client, patternsRepo, patternsFiles string) str
 				continue
 			}
 
-			files, err := client.GetAllFilesInPath(owner, repo, path)
+			files, err := client.GetAllFilesInPath(ctx, owner, repo, path)
 			if err != nil {
 				log.Printf("Warning: could not fetch %s from %s: %v", path, repoRef, err)
 				continue
@@ -279,3 +316,13 @@ func envOrDefaultFloat(key string, defaultVal float64) float64 {
 	}
 	return defaultVal
 }
+
+func envOrDefaultInt(key string, defaultVal int) int {
+	if v := os.Getenv(key); v != "" {
+		i, err := strconv.Atoi(v)
+		if err == nil {
+			return i
+		}
+	}
+	return defaultVal
+}

gitea/client.go

@@ -1,26 +1,35 @@
+// Package gitea provides a client for the Gitea API.
+// It supports pull request operations, file content retrieval,
+// and review submission.
 package gitea
 
 import (
+	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
+	"log"
 	"net/http"
+	"net/url"
 	"strings"
+	"time"
 )
 
 // Client interacts with the Gitea API.
+// A Client is safe for concurrent use by multiple goroutines.
 type Client struct {
-	BaseURL string
-	Token   string
-	HTTP    *http.Client
+	baseURL string
+	token   string
+	http    *http.Client
 }
 
 // NewClient creates a new Gitea API client.
 func NewClient(baseURL, token string) *Client {
 	return &Client{
-		BaseURL: strings.TrimRight(baseURL, "/"),
-		Token:   token,
-		HTTP:    &http.Client{},
+		baseURL: strings.TrimRight(baseURL, "/"),
+		token:   token,
+		http:    &http.Client{Timeout: 30 * time.Second},
 	}
 }
 
@@ -49,9 +58,9 @@ type ChangedFile struct {
 }
 
 // GetPullRequest fetches PR metadata.
-func (c *Client) GetPullRequest(owner, repo string, number int) (*PullRequest, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d", c.BaseURL, owner, repo, number)
-	body, err := c.doGet(url)
+func (c *Client) GetPullRequest(ctx context.Context, owner, repo string, number int) (*PullRequest, error) {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d", c.baseURL, owner, repo, number)
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return nil, fmt.Errorf("fetch PR: %w", err)
 	}
@@ -63,9 +72,9 @@ func (c *Client) GetPullRequest(owner, repo string, number int) (*PullRequest, e
 }
 
 // GetPullRequestDiff fetches the unified diff for a PR.
-func (c *Client) GetPullRequestDiff(owner, repo string, number int) (string, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d.diff", c.BaseURL, owner, repo, number)
-	body, err := c.doGet(url)
+func (c *Client) GetPullRequestDiff(ctx context.Context, owner, repo string, number int) (string, error) {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d.diff", c.baseURL, owner, repo, number)
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return "", fmt.Errorf("fetch diff: %w", err)
 	}
@@ -73,9 +82,9 @@ func (c *Client) GetPullRequestDiff(owner, repo string, number int) (string, err
 }
 
 // GetPullRequestFiles fetches the list of files changed in a PR.
-func (c *Client) GetPullRequestFiles(owner, repo string, number int) ([]ChangedFile, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d/files", c.BaseURL, owner, repo, number)
-	body, err := c.doGet(url)
+func (c *Client) GetPullRequestFiles(ctx context.Context, owner, repo string, number int) ([]ChangedFile, error) {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d/files", c.baseURL, owner, repo, number)
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return nil, fmt.Errorf("fetch PR files: %w", err)
 	}
@@ -87,9 +96,9 @@ func (c *Client) GetPullRequestFiles(owner, repo string, number int) ([]ChangedF
 }
 
 // GetCommitStatuses fetches CI statuses for a commit SHA.
-func (c *Client) GetCommitStatuses(owner, repo, sha string) ([]CommitStatus, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/commits/%s/statuses", c.BaseURL, owner, repo, sha)
-	body, err := c.doGet(url)
+func (c *Client) GetCommitStatuses(ctx context.Context, owner, repo, sha string) ([]CommitStatus, error) {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/commits/%s/statuses", c.baseURL, owner, repo, sha)
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return nil, fmt.Errorf("fetch commit statuses: %w", err)
 	}
@@ -101,9 +110,9 @@ func (c *Client) GetCommitStatuses(owner, repo, sha string) ([]CommitStatus, err
 }
 
 // GetFileContent fetches a file from the default branch of a repo.
-func (c *Client) GetFileContent(owner, repo, filepath string) (string, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/raw/%s", c.BaseURL, owner, repo, filepath)
-	body, err := c.doGet(url)
+func (c *Client) GetFileContent(ctx context.Context, owner, repo, filepath string) (string, error) {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/raw/%s", c.baseURL, owner, repo, escapePath(filepath))
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return "", fmt.Errorf("fetch file %s: %w", filepath, err)
 	}
@@ -111,9 +120,9 @@ func (c *Client) GetFileContent(owner, repo, filepath string) (string, error) {
 }
 
 // GetFileContentRef fetches a file from a specific ref (branch/tag/sha) in a repo.
-func (c *Client) GetFileContentRef(owner, repo, filepath, ref string) (string, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/raw/%s?ref=%s", c.BaseURL, owner, repo, filepath, ref)
-	body, err := c.doGet(url)
+func (c *Client) GetFileContentRef(ctx context.Context, owner, repo, filepath, ref string) (string, error) {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/raw/%s?ref=%s", c.baseURL, owner, repo, escapePath(filepath), url.QueryEscape(ref))
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return "", fmt.Errorf("fetch file %s@%s: %w", filepath, ref, err)
 	}
@@ -122,8 +131,8 @@ func (c *Client) GetFileContentRef(owner, repo, filepath, ref string) (string, e
 
 // PostReview submits a review to a PR.
 // event should be "APPROVED" or "REQUEST_CHANGES".
-func (c *Client) PostReview(owner, repo string, number int, event, body string) error {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d/reviews", c.BaseURL, owner, repo, number)
+func (c *Client) PostReview(ctx context.Context, owner, repo string, number int, event, body string) error {
+	reqURL := fmt.Sprintf("%s/api/v1/repos/%s/%s/pulls/%d/reviews", c.baseURL, owner, repo, number)
 
 	payload := struct {
 		Body  string `json:"body"`
@@ -138,14 +147,14 @@ func (c *Client) PostReview(owner, repo string, number int, event, body string)
 		return fmt.Errorf("marshal review payload: %w", err)
 	}
 
-	req, err := http.NewRequest("POST", url, strings.NewReader(string(data)))
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, reqURL, bytes.NewReader(data))
 	if err != nil {
 		return fmt.Errorf("create review request: %w", err)
 	}
-	req.Header.Set("Authorization", "token "+c.Token)
+	req.Header.Set("Authorization", "token "+c.token)
 	req.Header.Set("Content-Type", "application/json")
 
-	resp, err := c.HTTP.Do(req)
+	resp, err := c.http.Do(req)
 	if err != nil {
 		return fmt.Errorf("post review: %w", err)
 	}
@@ -158,14 +167,14 @@ func (c *Client) PostReview(owner, repo string, number int, event, body string)
 	return nil
 }
 
-func (c *Client) doGet(url string) ([]byte, error) {
-	req, err := http.NewRequest("GET", url, nil)
+func (c *Client) doGet(ctx context.Context, reqURL string) ([]byte, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, reqURL, nil)
 	if err != nil {
 		return nil, err
 	}
-	req.Header.Set("Authorization", "token "+c.Token)
+	req.Header.Set("Authorization", "token "+c.token)
 
-	resp, err := c.HTTP.Do(req)
+	resp, err := c.http.Do(req)
 	if err != nil {
 		return nil, err
 	}
@@ -178,6 +187,18 @@ func (c *Client) doGet(url string) ([]byte, error) {
 	return io.ReadAll(resp.Body)
 }
 
+// escapePath escapes each segment of a relative file path for use in URLs.
+// Slashes are preserved as path separators; other special characters are escaped.
+// Input should be a relative path (no leading slash). Already-encoded segments
+// will be double-encoded, which is the desired behavior for user-provided paths.
+func escapePath(p string) string {
+	parts := strings.Split(p, "/")
+	for i, part := range parts {
+		parts[i] = url.PathEscape(part)
+	}
+	return strings.Join(parts, "/")
+}
+
 // ContentEntry represents a file or directory entry from the contents API.
 type ContentEntry struct {
 	Name string `json:"name"`
@@ -186,9 +207,15 @@ type ContentEntry struct {
 }
 
 // ListContents lists files and directories at a given path in a repo.
-func (c *Client) ListContents(owner, repo, path string) ([]ContentEntry, error) {
-	url := fmt.Sprintf("%s/api/v1/repos/%s/%s/contents/%s", c.BaseURL, owner, repo, path)
-	body, err := c.doGet(url)
+// Pass an empty path to list the repository root.
+func (c *Client) ListContents(ctx context.Context, owner, repo, path string) ([]ContentEntry, error) {
+	var reqURL string
+	if path == "" {
+		reqURL = fmt.Sprintf("%s/api/v1/repos/%s/%s/contents", c.baseURL, owner, repo)
+	} else {
+		reqURL = fmt.Sprintf("%s/api/v1/repos/%s/%s/contents/%s", c.baseURL, owner, repo, escapePath(path))
+	}
+	body, err := c.doGet(ctx, reqURL)
 	if err != nil {
 		return nil, fmt.Errorf("list contents %s: %w", path, err)
 	}
@@ -202,14 +229,14 @@ func (c *Client) ListContents(owner, repo, path string) ([]ContentEntry, error)
 // GetAllFilesInPath recursively fetches all file contents under a path.
 // If the path is a file, returns just that file's content.
 // If the path is a directory, recursively fetches all files within it.
-func (c *Client) GetAllFilesInPath(owner, repo, path string) (map[string]string, error) {
+func (c *Client) GetAllFilesInPath(ctx context.Context, owner, repo, path string) (map[string]string, error) {
 	results := make(map[string]string)
 
 	// Try listing as directory first
-	entries, err := c.ListContents(owner, repo, path)
+	entries, err := c.ListContents(ctx, owner, repo, path)
 	if err != nil {
 		// Might be a file, try fetching directly
-		content, fileErr := c.GetFileContent(owner, repo, path)
+		content, fileErr := c.GetFileContent(ctx, owner, repo, path)
 		if fileErr != nil {
 			return nil, fmt.Errorf("path %q is neither a file nor directory: %w", path, err)
 		}
@@ -220,14 +247,16 @@ func (c *Client) GetAllFilesInPath(owner, repo, path string) (map[string]string,
 	for _, entry := range entries {
 		switch entry.Type {
 		case "file":
-			content, err := c.GetFileContent(owner, repo, entry.Path)
+			content, err := c.GetFileContent(ctx, owner, repo, entry.Path)
 			if err != nil {
-				continue // Skip files we can't read
+				log.Printf("Warning: could not fetch file %s: %v", entry.Path, err)
+				continue
 			}
 			results[entry.Path] = content
 		case "dir":
-			subResults, err := c.GetAllFilesInPath(owner, repo, entry.Path)
+			subResults, err := c.GetAllFilesInPath(ctx, owner, repo, entry.Path)
 			if err != nil {
+				log.Printf("Warning: could not recurse into %s: %v", entry.Path, err)
 				continue
 			}
 			for k, v := range subResults {

gitea/client_test.go

@@ -1,6 +1,7 @@
 package gitea
 
 import (
+	"context"
 	"encoding/json"
 	"fmt"
 	"net/http"
@@ -28,7 +29,7 @@ func TestGetPullRequest(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	got, err := client.GetPullRequest("owner", "repo", 1)
+	got, err := client.GetPullRequest(context.Background(), "owner", "repo", 1)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -55,7 +56,7 @@ func TestGetPullRequestDiff(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	got, err := client.GetPullRequestDiff("owner", "repo", 5)
+	got, err := client.GetPullRequestDiff(context.Background(), "owner", "repo", 5)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -80,7 +81,7 @@ func TestGetCommitStatuses(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	got, err := client.GetCommitStatuses("owner", "repo", "abc123")
+	got, err := client.GetCommitStatuses(context.Background(), "owner", "repo", "abc123")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -127,7 +128,7 @@ func TestPostReview(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	err := client.PostReview("owner", "repo", 3, "APPROVED", "LGTM")
+	err := client.PostReview(context.Background(), "owner", "repo", 3, "APPROVED", "LGTM")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -141,7 +142,7 @@ func TestGetPullRequest_Non200(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	_, err := client.GetPullRequest("owner", "repo", 999)
+	_, err := client.GetPullRequest(context.Background(), "owner", "repo", 999)
 	if err == nil {
 		t.Fatal("expected error for 404, got nil")
 	}
@@ -154,7 +155,7 @@ func TestGetPullRequest_BadJSON(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	_, err := client.GetPullRequest("owner", "repo", 1)
+	_, err := client.GetPullRequest(context.Background(), "owner", "repo", 1)
 	if err == nil {
 		t.Fatal("expected error for bad JSON, got nil")
 	}
@@ -168,7 +169,7 @@ func TestPostReview_Non200(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	err := client.PostReview("owner", "repo", 1, "APPROVED", "test")
+	err := client.PostReview(context.Background(), "owner", "repo", 1, "APPROVED", "test")
 	if err == nil {
 		t.Fatal("expected error for 403, got nil")
 	}
@@ -186,7 +187,7 @@ func TestGetFileContent(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	got, err := client.GetFileContent("owner", "repo", "CONVENTIONS.md")
+	got, err := client.GetFileContent(context.Background(), "owner", "repo", "CONVENTIONS.md")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -206,7 +207,7 @@ func TestGetPullRequestFiles(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	files, err := client.GetPullRequestFiles("owner", "repo", 1)
+	files, err := client.GetPullRequestFiles(context.Background(), "owner", "repo", 1)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -231,7 +232,7 @@ func TestGetFileContentRef(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	content, err := client.GetFileContentRef("owner", "repo", "main.go", "feature-branch")
+	content, err := client.GetFileContentRef(context.Background(), "owner", "repo", "main.go", "feature-branch")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -251,7 +252,7 @@ func TestListContents(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	entries, err := client.ListContents("owner", "repo", "docs")
+	entries, err := client.ListContents(context.Background(), "owner", "repo", "docs")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -282,7 +283,7 @@ func TestGetAllFilesInPath_File(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-token")
-	files, err := client.GetAllFilesInPath("owner", "repo", "README.md")
+	files, err := client.GetAllFilesInPath(context.Background(), "owner", "repo", "README.md")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -293,3 +294,27 @@ func TestGetAllFilesInPath_File(t *testing.T) {
 		t.Errorf("unexpected content: %q", files["README.md"])
 	}
 }
+
+func TestEscapePath(t *testing.T) {
+	tests := []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{"simple", "src/main.go", "src/main.go"},
+		{"spaces", "my dir/my file.go", "my%20dir/my%20file.go"},
+		{"special chars", "path/file#1.txt", "path/file%231.txt"},
+		{"empty", "", ""},
+		{"single segment", "README.md", "README.md"},
+		{"nested deep", "a/b/c/d.md", "a/b/c/d.md"},
+		{"already encoded", "path/file%20name.go", "path/file%2520name.go"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := escapePath(tt.input)
+			if got != tt.want {
+				t.Errorf("escapePath(%q) = %q, want %q", tt.input, got, tt.want)
+			}
+		})
+	}
+}

integration_test.go

@@ -3,8 +3,10 @@
 package main
 
 import (
+	"context"
 	"os"
 	"strconv"
+	"strings"
 	"testing"
 
 	"gitea.weiker.me/rodin/review-bot/gitea"
@@ -42,28 +44,27 @@ func TestIntegration_FullReviewFlow(t *testing.T) {
 	}
 
 	// Parse owner/repo
-	owner, repoName := "", ""
-	for i, c := range giteaRepo {
-		if c == / {
-			owner = giteaRepo[:i]
-			repoName = giteaRepo[i+1:]
-			break
-		}
+	parts := strings.SplitN(giteaRepo, "/", 2)
+	if len(parts) != 2 {
+		t.Fatalf("Invalid repo format %q", giteaRepo)
 	}
+	owner, repoName := parts[0], parts[1]
 	if owner == "" || repoName == "" {
 		t.Fatalf("Invalid repo format %q", giteaRepo)
 	}
 
+	ctx := context.Background()
+
 	// Step 1: Fetch PR
 	giteaClient := gitea.NewClient(giteaURL, giteaToken)
-	pr, err := giteaClient.GetPullRequest(owner, repoName, prNumber)
+	pr, err := giteaClient.GetPullRequest(ctx, owner, repoName, prNumber)
 	if err != nil {
 		t.Fatalf("GetPullRequest: %v", err)
 	}
 	t.Logf("PR: %s (sha: %s)", pr.Title, pr.Head.Sha)
 
 	// Step 2: Fetch diff
-	diff, err := giteaClient.GetPullRequestDiff(owner, repoName, prNumber)
+	diff, err := giteaClient.GetPullRequestDiff(ctx, owner, repoName, prNumber)
 	if err != nil {
 		t.Fatalf("GetPullRequestDiff: %v", err)
 	}
@@ -73,12 +74,12 @@ func TestIntegration_FullReviewFlow(t *testing.T) {
 	t.Logf("Diff size: %d bytes", len(diff))
 
 	// Step 3: Build prompts
-	systemPrompt := review.BuildSystemPrompt("")
-	userPrompt := review.BuildUserPrompt(pr.Title, pr.Body, diff, true, "")
+	systemPrompt := review.BuildSystemPrompt("", "")
+	userPrompt := review.BuildUserPrompt(pr.Title, pr.Body, diff, "", true, "")
 
 	// Step 4: Call LLM
 	llmClient := llm.NewClient(llmBaseURL, llmAPIKey, llmModel)
-	response, err := llmClient.Complete([]llm.Message{
+	response, err := llmClient.Complete(ctx, []llm.Message{
 		{Role: "system", Content: systemPrompt},
 		{Role: "user", Content: userPrompt},
 	})

llm/client.go

@@ -1,36 +1,47 @@
+// Package llm provides a client for OpenAI-compatible chat completion APIs.
 package llm
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
 	"strings"
+	"time"
 )
 
 // Client calls an OpenAI-compatible chat completion API.
+// A Client is safe for concurrent use by multiple goroutines after construction.
+// WithTimeout and WithTemperature must be called during setup, before concurrent use.
 type Client struct {
-	BaseURL string
-	APIKey  string
-	Model   string
-	Temperature float64
-	HTTP    *http.Client
+	baseURL     string
+	apiKey      string
+	model       string
+	temperature float64
+	http        *http.Client
 }
 
 // NewClient creates a new LLM client.
 func NewClient(baseURL, apiKey, model string) *Client {
 	return &Client{
-		BaseURL: strings.TrimRight(baseURL, "/"),
-		APIKey:  apiKey,
-		Model:   model,
-		HTTP:    &http.Client{},
+		baseURL: strings.TrimRight(baseURL, "/"),
+		apiKey:  apiKey,
+		model:   model,
+		http:    &http.Client{Timeout: 5 * time.Minute},
 	}
 }
 
+// WithTimeout sets the HTTP request timeout for LLM calls (default 5 minutes).
+func (c *Client) WithTimeout(d time.Duration) *Client {
+	c.http.Timeout = d
+	return c
+}
+
 // WithTemperature sets the temperature for LLM requests (0 = omit, uses server default).
 func (c *Client) WithTemperature(t float64) *Client {
-	c.Temperature = t
+	c.temperature = t
 	return c
 }
 
@@ -57,12 +68,11 @@ type ChatResponse struct {
 }
 
 // Complete sends a chat completion request and returns the assistant's response content.
-func (c *Client) Complete(messages []Message) (string, error) {
+func (c *Client) Complete(ctx context.Context, messages []Message) (string, error) {
 	reqBody := ChatRequest{
-		Model:       c.Model,
-		Temperature: c.Temperature,
+		Model:       c.model,
+		Temperature: c.temperature,
 		Messages:    messages,
-		
 	}
 
 	data, err := json.Marshal(reqBody)
@@ -70,15 +80,15 @@ func (c *Client) Complete(messages []Message) (string, error) {
 		return "", fmt.Errorf("marshal request: %w", err)
 	}
 
-	url := c.BaseURL + "/chat/completions"
-	req, err := http.NewRequest("POST", url, bytes.NewReader(data))
+	url := c.baseURL + "/chat/completions"
+	req, err := http.NewRequestWithContext(ctx, "POST", url, bytes.NewReader(data))
 	if err != nil {
 		return "", fmt.Errorf("create request: %w", err)
 	}
-	req.Header.Set("Authorization", "Bearer "+c.APIKey)
+	req.Header.Set("Authorization", "Bearer "+c.apiKey)
 	req.Header.Set("Content-Type", "application/json")
 
-	resp, err := c.HTTP.Do(req)
+	resp, err := c.http.Do(req)
 	if err != nil {
 		return "", fmt.Errorf("LLM request: %w", err)
 	}

llm/client_test.go

@@ -1,10 +1,12 @@
 package llm
 
 import (
+	"context"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
 	"testing"
+	"time"
 )
 
 func TestComplete_Success(t *testing.T) {
@@ -51,7 +53,7 @@ func TestComplete_Success(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-key", "gpt-4")
-	got, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	got, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -68,7 +70,7 @@ func TestComplete_APIError(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-key", "gpt-4")
-	_, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	_, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err == nil {
 		t.Fatal("expected error for 429, got nil")
 	}
@@ -82,7 +84,7 @@ func TestComplete_NoChoices(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-key", "gpt-4")
-	_, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	_, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err == nil {
 		t.Fatal("expected error for no choices, got nil")
 	}
@@ -95,7 +97,7 @@ func TestComplete_BadJSON(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "test-key", "gpt-4")
-	_, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	_, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err == nil {
 		t.Fatal("expected error for bad JSON, got nil")
 	}
@@ -103,7 +105,7 @@ func TestComplete_BadJSON(t *testing.T) {
 
 func TestComplete_ServerDown(t *testing.T) {
 	client := NewClient("http://127.0.0.1:1", "test-key", "gpt-4")
-	_, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	_, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err == nil {
 		t.Fatal("expected error for connection refused, got nil")
 	}
@@ -111,16 +113,16 @@ func TestComplete_ServerDown(t *testing.T) {
 
 func TestWithTemperature(t *testing.T) {
 	client := NewClient("http://example.com", "key", "model")
-	if client.Temperature != 0 {
-		t.Errorf("expected initial temperature 0, got %f", client.Temperature)
+	if client.temperature != 0 {
+		t.Errorf("expected initial temperature 0, got %f", client.temperature)
 	}
 
 	result := client.WithTemperature(0.7)
 	if result != client {
 		t.Error("WithTemperature should return the same client for chaining")
 	}
-	if client.Temperature != 0.7 {
-		t.Errorf("expected temperature 0.7, got %f", client.Temperature)
+	if client.temperature != 0.7 {
+		t.Errorf("expected temperature 0.7, got %f", client.temperature)
 	}
 }
 
@@ -147,7 +149,7 @@ func TestComplete_TemperatureOmittedWhenZero(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "key", "model")
-	_, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	_, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -180,8 +182,29 @@ func TestComplete_TemperatureIncludedWhenSet(t *testing.T) {
 	defer server.Close()
 
 	client := NewClient(server.URL, "key", "model").WithTemperature(0.7)
-	_, err := client.Complete([]Message{{Role: "user", Content: "Hi"}})
+	_, err := client.Complete(context.Background(), []Message{{Role: "user", Content: "Hi"}})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
 }
+
+func TestWithTimeout(t *testing.T) {
+	client := NewClient("http://example.com", "key", "model")
+	result := client.WithTimeout(10 * time.Second)
+	if result != client {
+		t.Error("WithTimeout should return the same client for chaining")
+	}
+	// Verify timeout causes failure on slow server
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		time.Sleep(200 * time.Millisecond)
+		w.Header().Set("Content-Type", "application/json")
+		w.Write([]byte(`{"choices":[{"message":{"content":"ok"}}]}`))
+	}))
+	defer server.Close()
+
+	shortClient := NewClient(server.URL, "key", "model").WithTimeout(50 * time.Millisecond)
+	_, err := shortClient.Complete(context.Background(), []Message{{Role: "user", Content: "hi"}})
+	if err == nil {
+		t.Error("expected timeout error with 50ms timeout and 200ms server delay")
+	}
+}

review/prompt.go

@@ -1,3 +1,5 @@
+// Package review builds prompts for AI code review and parses LLM responses
+// into structured review results.
 package review
 
 import (
@@ -5,8 +7,10 @@ import (
 	"strings"
 )
 
-// BuildSystemPrompt constructs the system prompt for the LLM reviewer.
-func BuildSystemPrompt(conventions, patterns string) string {
+// BuildSystemBase returns the core system prompt instructions without
+// patterns or conventions. Used by the budget package to separate
+// trimmable from non-trimmable content.
+func BuildSystemBase() string {
 	var sb strings.Builder
 
 	sb.WriteString("You are an expert code reviewer. Review the provided pull request diff carefully.\n\n")
@@ -40,6 +44,15 @@ func BuildSystemPrompt(conventions, patterns string) string {
 	sb.WriteString("- Line numbers should reference the new file line numbers from the diff headers.\n")
 	sb.WriteString("- If the diff is empty or trivial (only formatting/whitespace), APPROVE with no findings.\n")
 
+	return sb.String()
+}
+
+// BuildSystemPrompt constructs the full system prompt with patterns and conventions.
+// Deprecated: Use BuildSystemBase with budget.Fit for context-aware assembly.
+func BuildSystemPrompt(conventions, patterns string) string {
+	var sb strings.Builder
+	sb.WriteString(BuildSystemBase())
+
 	if patterns != "" {
 		sb.WriteString(fmt.Sprintf("\n\n## Language Patterns & Idioms\n\nUse the following patterns as review criteria. Code that violates these established patterns is a finding:\n\n%s\n", patterns))
 	}
@@ -51,8 +64,9 @@ func BuildSystemPrompt(conventions, patterns string) string {
 	return sb.String()
 }
 
-// BuildUserPrompt constructs the user message with PR context.
-func BuildUserPrompt(title, description, diff, fileContext string, ciPassed bool, ciDetails string) string {
+// BuildUserMeta returns the PR metadata header (title, description, CI status)
+// without the diff or file context. Used by the budget package.
+func BuildUserMeta(title, description string, ciPassed bool, ciDetails string) string {
 	var sb strings.Builder
 
 	sb.WriteString(fmt.Sprintf("## Pull Request: %s\n\n", title))
@@ -71,6 +85,16 @@ func BuildUserPrompt(title, description, diff, fileContext string, ciPassed bool
 		sb.WriteString(fmt.Sprintf("CI Details: %s\n", ciDetails))
 	}
 
+	return sb.String()
+}
+
+// BuildUserPrompt constructs the user message with PR context.
+// Deprecated: Use BuildUserMeta with budget.Fit for context-aware assembly.
+func BuildUserPrompt(title, description, diff, fileContext string, ciPassed bool, ciDetails string) string {
+	var sb strings.Builder
+
+	sb.WriteString(BuildUserMeta(title, description, ciPassed, ciDetails))
+
 	if fileContext != "" {
 		sb.WriteString("\n### Full File Context (modified files)\n\n")
 		sb.WriteString(fileContext)

review/prompt_test.go

@@ -116,3 +116,43 @@ func TestBuildUserPrompt_WithoutFileContext(t *testing.T) {
 		t.Error("should not include file context section when empty")
 	}
 }
+
+
+func TestBuildSystemBase(t *testing.T) {
+	result := BuildSystemBase()
+	if result == "" {
+		t.Fatal("BuildSystemBase returned empty string")
+	}
+	if !strings.Contains(result, "expert code reviewer") {
+		t.Error("expected reviewer role in system base")
+	}
+	if !strings.Contains(result, "REQUEST_CHANGES") {
+		t.Error("expected verdict format in system base")
+	}
+	if !strings.Contains(result, "JSON") {
+		t.Error("expected JSON output instruction in system base")
+	}
+}
+
+func TestBuildUserMeta(t *testing.T) {
+	result := BuildUserMeta("Fix bug", "Some description", true, "all checks passed")
+	if !strings.Contains(result, "Fix bug") {
+		t.Error("expected title in user meta")
+	}
+	if !strings.Contains(result, "Some description") {
+		t.Error("expected description in user meta")
+	}
+	if !strings.Contains(result, "PASSED") {
+		t.Error("expected CI PASSED status")
+	}
+}
+
+func TestBuildUserMeta_CIFailed(t *testing.T) {
+	result := BuildUserMeta("Title", "", false, "test job failed")
+	if !strings.Contains(result, "FAILED") {
+		t.Error("expected CI FAILED status")
+	}
+	if strings.Contains(result, "Description") {
+		t.Error("expected no description section when empty")
+	}
+}