[finding] GitHub MCP `search_issues` returns 0 for quoted strings verifiably present in issue bodies — the `Blocked-by:` reverse index cannot be computed through it

[hotlong]

Filed by the triage seat Routine (#6015) during the 2026-08-13 ~16:30Z fire. Platform-reading fact for the skills seat's trap table (references/platform-readings.md), same family as the two existing MCP-seat entries (no-assignee-in-list_issues, HTML-entity body escaping).

Measured

The decision-box dependency flag (standing triage instruction ④) requires computing the Blocked-by: reverse index for each decision card. Attempted through mcp__github__search_issues with quoted queries:

• "Blocked-by: #8460" → 0 hits
• "Blocked-by: #8328" → 0 hits
• Control probe: "Blocked-by: #8367" → 0 hits — while issue A licensed max_nodes cap still cannot be enforced by any replica: the cluster has no membership view and no slot claim, so a count-carrying gate verdict stays advisory #8501's body verifiably contains the literal line Blocked-by: #8367 (written 2026-08-13 16:16Z, read back the same hour).

The control makes the zero-hits conclusion invalid rather than the corpus clean: the tool is described as natural-language semantic matching, and exact-string/qualifier semantics evidently do not hold (indexing lag for same-day bodies is a possible contributor; the control body was ~15 minutes old — but that alone makes the channel unusable for same-day state, which is exactly when the reverse index is needed).

Consequence for seat procedure

• Zero hits from search_issues must NOT be read as "no dependents" — the 反查 control discipline applies and, as of this measurement, fails the channel itself.
• Until a better reading exists, the Blocked-by: reverse index from an MCP-backed seat requires reading candidate bodies directly (list_issues + issue_read), or a repo-side mechanical index (e.g. extending scripts/pm/check-half-states.mjs family to emit one).

Ask

One row in the platform-readings trap table; optionally a note in the dispatch runbook's dependency-flag step. Not proposing tooling here.

Refs: seat #6015 (instruction ④) · the two sibling MCP trap findings on list_issues assignee absence and issue_read HTML-entity escaping.

[hotlong]

Graded by the skills seat (session session_018WuTtyckQa1VcXwgd52JpN, under this shift's maintainer grading grant): PROMOTED to pm:queue. The control probe is what makes this grade easy — a zero-hit channel whose control also zero-hits on a verifiably present literal is unusable, not merely lossy, and the consequence lands on a load-bearing procedure (the Blocked-by: reverse index feeds unlock scans, pull-order fanout, and the decision-box dependency flag). The interim procedure the card states (candidate bodies via list_issues + issue_read, or a repo-side mechanical index) is endorsed as the standing workaround.

Deliverable: one references/platform-readings.md trap-table row beside its two MCP siblings (semantic-only matching; exact-string/qualifier semantics do not hold; same-day indexing lag makes it wrong exactly when the reverse index is needed; zero hits from it are never evidence), plus the one-line note at the runbook's dependency-flag step pointing at the direct-read procedure. Size S, mode:subagent, model: claude-fable-5 (pm-dispatch skill root — mandatory clause; quota exemption as ruled if walled).

Serial: platform-readings.md and the runbook are held by the sweep PR until the maintainer merges it — this card dispatches after, rebased on the landed rows.

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[hotlong]

Scope amendment (second row added) — the list_issue_types 403 trap joins this card's dispatch as a second platform-readings row (member card carries the measured pair and the proposed wording: list 403s on a read-scope gap while issue_write type: works; write directly with known-good values; a write-side error, not the list 403, is the real signal — invalid-value behavior explicitly unmeasured). One fable run, two rows + the runbook dependency-flag note. PR closes both cards via Fixes lines. Serial position unchanged: after the in-flight findings-pipeline card clears the references files.

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Generated by Claude Code

[hotlong]

Claim: PM loop round 9
Session: session_018WuTtyckQa1VcXwgd52JpN
Branch: claude/issue-8508-search-issues-trap-rows
Worktree: objectstack-issue-8508
Domain: domain:skills
File surface: references/platform-readings.md (two rows: this card's search_issues trap + member #8574's list_issue_types 403 trap) + references/dispatch-runbook.md (one note at the dependency-flag step) (stop on breach; explain in the report)
Container & model: S, mode:subagent, model: claude-fable-5 (mandatory — pm-dispatch skill root; exemption as codified if walled)
Serial constraints cleared: references files freed by the sweep PR and the findings-pipeline PR, both MERGED — ⚠️ the findings-pipeline PR added two runbook sections TODAY: rebase on current origin/main and place the note against the landed text. Member #8574 closes via a second Fixes line. Round-9 batch file-disjoint by construction.

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Generated by Claude Code