- budget/budget_test.go: add TestFit_DesignDocsInSystemPrompt,
TestFit_DesignDocsTrimmedBeforeFileContext, TestFit_DesignDocsEmptyNoHeading
to cover the new DesignDocs section through Fit() and buildResult()
- Remove PLAN-137.md (contained raw thinking stream, not suitable as repo doc)
- Add docs/DESIGN-137-doc-map.md with clean architectural decision record
- New --doc-map flag (DOC_MAP_FILE env var): path to YAML config mapping
source path globs to governing design docs
- New --doc-map-max-bytes flag (DOC_MAP_MAX_BYTES env var): cap on total
injected doc content, default 100KB
- review/docmap.go: DocMapConfig parsing, glob matching with ** support,
doc loading via VCS with directory expansion and size guard
- budget.Sections: new DesignDocs field, trimmed after conventions
- budget.buildResult: injects DesignDocs under ## Design Documents heading
- action.yml: doc-map and doc-map-max-bytes inputs wired to env vars
- CHANGELOG.md: created with unreleased entry
- Tests: ParseDocMapConfig, MatchDocs, globMatch, LoadMatchingDocs
- UserMeta comment: "never trimmed" → "truncated only if base exceeds budget"
- Skip diff truncation marker when diffBudget < markerBudget (prevents
marker itself from pushing EstTokens over the limit)
- Rename filepath → filePath to avoid shadowing stdlib package name
- Account for truncation marker tokens when computing diff budget
(prevents EstTokens exceeding model limit in edge cases)
- Rune-safe truncation for both UserMeta and Diff (no split multi-byte)
- Fix misleading comment (1000 chars → ~1000 tokens/4000 chars)
- Extract marker strings as constants
- Add unit tests for BuildSystemBase and BuildUserMeta
Addresses review findings:
- Replace map-based model limits with ordered slice (longest-prefix-first)
for deterministic matching
- Truncate UserMeta when base content alone exceeds budget (keeps first
4000 chars + truncation marker)
- Remove hard minimum of 1000 tokens for diff budget — use 0 as floor
to guarantee total never exceeds limit
- Handle zero-budget edge case (diff replaced with manual-review message)
- Add tests: huge UserMeta, all-sections-huge never exceeds limit
Adds a budget package that estimates token usage and progressively
trims context to fit within model-specific limits.
Trim order (least important first):
1. Language patterns
2. Repository conventions
3. Full file context
4. Diff (truncated as last resort)
When content is trimmed, a note is appended to the user prompt so
the LLM knows context was reduced.
- New budget package with Fit(), EstimateTokens(), LimitForModel()
- Model limit table (GPT-4.1: 128K, GPT-5: 200K, Claude: 200K)
- Refactored review/prompt.go: BuildSystemBase() and BuildUserMeta()
extract non-trimmable content; old functions delegate to new ones
- main.go uses budget.Fit() instead of direct prompt assembly
- 7 unit tests covering all trim paths
Closes#19
claw
Rodin