Verification — fix-pagination-clamp-signal

Worktree

• Path: E:/AMS/.worktrees/claude/fix-pagination-clamp-signal
• Branch: feature/fix-pagination-clamp-signal
• Base: origin/main @ 86e430fb

Commits (5-step chain)

Step	SHA	Subject
1. Audit	a2dfde1b	audit(fix-pagination-clamp-signal): inventory surface
2. Contract	a66acecc	contract(fix-pagination-clamp-signal): behavioral contract
3. Packet	94cc90ea	packet(fix-pagination-clamp-signal): execution plan
4. Implement	caf4c233	feat(fix-pagination-clamp-signal): surface clamped_limit signal
5. Verify	(this commit)	verify(fix-pagination-clamp-signal): test evidence

Acceptance criteria — verification

#	Criterion	Status	Evidence
1	listTasks signals clamping (option (a))	✅	src/domains/tasks/repository.ts:135-152 defines ListTasksResult interface; listTasks (line 552) returns {tasks, clamped_limit}.
2	task_list MCP payload includes clamped_limit	✅	src/domains/tasks/repository.ts:792-809 task_list handler returns {tasks, total_count, clamped_limit}.
3	INFO log line emitted on clamp via ctx.logger	✅	src/domains/tasks/repository.ts:802-806: ctx.logger(\[task_list] clamped limit: requested=${result.clamped_limit} max=${MAX_LIMIT}`). Emitted only when clamped_limit !== null`.
4	Required tests	✅	See test inventory below.
5	Backwards compatibility	✅	data.tasks and data.total_count unchanged; only data.clamped_limit added.
6	All gates pass (npm run build && npm run lint && npm test)	✅	See gate summary below.

Test inventory

Repository tests (src/__tests__/domains/tasks/repository.test.ts)

Pre-existing listTasks tests adapted to new return shape: 12.

New tests added (5):

1. clamps limit > 500 to 500 and signals clamped_limit — extended existing test.
2. returns clamped_limit=null when limit ≤ MAX_LIMIT (in-range) — new.
3. returns clamped_limit=null when limit is unspecified (default) — new.
4. boundary: limit=500 is NOT clamped (strict >) — new.
5. just-over: limit=501 yields clamped_limit=501 — new.

Total it() blocks in file: 56 → 60 (net +4 new — the existing clamp test was extended in place).

Tool tests (src/__tests__/domains/tasks/tools.test.ts)

Pre-existing task_list handler behavior tests adapted to new return shape: 5.

Schema tests:

• Old: Zod schema rejects limit > 500 — flipped to Zod schema accepts limit > 500 (clamps in repository, no longer rejects).
• New: Zod schema still rejects limit ≤ 0 and non-integer (regression-guard for Zod’s .positive().int()).

New handler/envelope/logger tests (4):

1. payload includes clamped_limit field (null when in-range).
2. payload includes clamped_limit field (number when clamped).
3. emits one INFO log line via ctx.logger when limit is clamped.
4. emits NO log line when limit is not clamped.
5. registerTaskTools wires task_list with a handler that captures ctx.logger — sanity check that the registration plumbing places the spy logger into ctx.

Total it() blocks in file: 41 → 47 (net +6).

Gate summary

$ npm run build
> colibri@0.0.1 build
> tsc
(no output — clean)

$ npm run lint
> colibri@0.0.1 lint
> eslint src
(no output — clean)

$ npm test
Test Suites: 30 passed, 30 total
Tests:       1367 passed, 1367 total

Pre-task baseline at origin/main @ 86e430fb: 1357 tests (per memory R83). Post-task: 1367 tests = +10 net (+4 in repository.test.ts, +6 in tools.test.ts). Zero regressions in any other suite.

The known pre-existing flake (startup — subprocess smoke) was not observed during the verification run. Both the targeted-suite run and full-suite run completed green.

Files touched (final summary)

File	Lines	Kind
src/domains/tasks/repository.ts	+50 / -16	source
src/__tests__/domains/tasks/repository.test.ts	+44 / -25	test
src/__tests__/domains/tasks/tools.test.ts	+106 / -16	test
docs/audits/fix-pagination-clamp-signal-audit.md	+137 / -0	audit
docs/contracts/fix-pagination-clamp-signal-contract.md	+147 / -0	contract
docs/packets/fix-pagination-clamp-signal-packet.md	+246 / -0	packet
docs/verification/fix-pagination-clamp-signal-verification.md	(this file)	verification

Repository total: 4 source/test files + 4 doc files = 8.

Callers of listTasks adapted

Site	File	Treatment
Production handler	src/domains/tasks/repository.ts:792	Captures result, surfaces clamped_limit, emits INFO log.
Test (19 sites)	src/__tests__/domains/tasks/repository.test.ts	Destructure { tasks } or read result.tasks / result.clamped_limit.
Test (5 sites)	src/__tests__/domains/tasks/tools.test.ts	Same pattern.

No other consumers exist in the repository — the signal is purely additive at the SDK boundary.

Edge cases verified

• filter.limit = undefined (default 50) → clamped_limit === null. ✅
• filter.limit = 100 → clamped_limit === null. ✅
• filter.limit = 500 (boundary, exact) → clamped_limit === null. ✅ (strict >)
• filter.limit = 501 (just-over) → clamped_limit === 501. ✅
• filter.limit = 1000 → clamped_limit === 1000. ✅
• filter.limit = 10_000 → clamped_limit === 10_000. ✅

Invariants preserved

• MAX_LIMIT === 500 — unchanged.
• DEFAULT_LIMIT === 50 — unchanged.
• Server still returns at most 500 rows on any single call (memory bound preserved).
• Sort order, soft-delete discipline, prepared-statement cache — all unchanged.
• No DB schema change.
• No new MCP tool registered (count remains 14).
• Other β tools (task_create, task_get, task_update, task_next_actions) — untouched.
• Writeback enforcement, FSM, state-machine — untouched.

Residual risks / blockers

None.

The Zod schema relaxation (.max(500) removed) is the public API surface change: clients that previously got INVALID_PARAMS for limit > 500 now get a successful response (≤500 rows) plus the clamped_limit signal. This is the intended behaviour and matches the contract; the prior rejection masked the existing repository clamp from clients.

Writeback

Per CLAUDE.md §7. With no live MCP client attached, the writeback lands in this verification document and the PR body. Equivalent runtime data:

task_id: fix-pagination-clamp-signal
branch: feature/fix-pagination-clamp-signal
worktree: .worktrees/claude/fix-pagination-clamp-signal
commits:
  audit:    a2dfde1b
  contract: a66acecc
  packet:   94cc90ea
  feat:     caf4c233
  verify:   (this commit)
tests: npm run build && npm run lint && npm test (all green; 1367/1367)
summary: surfaces clamped_limit on listTasks result + task_list payload; relaxes Zod limit cap so the existing clamp becomes observable; emits one INFO log line per clamp event via ctx.logger; backwards compatible (additive payload field).
blockers: none