Intent-coherence sub-agent: flag unrelated content removals as potential rebase artifacts

[fullsend-ai-retro]

What happened

On PR #1611, human reviewer ralphbean caught two accidental content removals across separate review rounds: (1) step 2d 'Review prior triage analysis' was removed from triage.md — this had been specifically added by #1571 to fix issue #1491 and was unrelated to ADR 41; (2) the 'Verify API contracts per code path' checklist item was removed from code-implementation/SKILL.md — also unrelated to the PR's scope. Both were confirmed as rebase artifacts by the PR author. The review bot did not flag either removal across 4 review cycles.

What could go better

The intent-coherence sub-agent evaluates whether changes match the PR's stated scope, but it currently focuses on additions and modifications rather than scrutinizing deletions within modified files. In large rebased PRs that touch skill/configuration files for a specific purpose, content can be accidentally dropped during conflict resolution. This is distinct from #1741, which covers entire files appearing in the diff due to stale branches — here, the files were legitimately modified but contained unintended deletions of content added by other PRs. Medium confidence: distinguishing intentional cleanup from accidental removal requires nuanced judgment, but the pattern (removing procedural steps or checklist items unrelated to the PR's stated ADR/feature) is detectable.

Proposed change

Add guidance to skills/pr-review/sub-agents/intent-coherence.md: when a file is modified for a stated architectural purpose (e.g., 'align with ADR 41'), specifically scan for removals of functional content (numbered steps, checklist items, procedural instructions, configuration entries) that have no semantic connection to the PR's scope. Flag such removals as potential rebase artifacts or accidental deletions with medium severity, noting the removed content and asking the author to confirm intentionality.

Validation criteria

Run the intent-coherence sub-agent against a test diff that modifies a skills document for a specific purpose (e.g., updating dispatch references) but also removes an unrelated numbered step that was previously added to fix a specific issue. The sub-agent should flag the unrelated removal as a potential rebase artifact.

---

Generated by retro agent from fullsend-ai/fullsend#1611

[fullsend-ai-prioritize]

RICE Priority Score: 1.58

Score breakdown

Dimension	Score	Reasoning
Reach	1.5	The PR review agent's intent-coherence sub-agent is used across all PRs in the project. Rebase artifacts are a common occurrence in any team doing active development, so this gap affects multiple teams and contributors who rely on automated review to catch unintended changes.
Impact	1.5	Accidental content removals during rebase can silently revert important fixes (e.g., the removed step was specifically added by #1571 to fix #1491). The bot missed this across 4 review cycles, meaning the current workaround is manual human review which is unreliable. This is a significant pain point that can lead to regressions.
Confidence	0.7	The issue is well-described with two concrete examples, a clear proposed change targeting a specific sub-agent file, and defined validation criteria. Some uncertainty remains around how reliably the sub-agent can distinguish intentional cleanup from accidental removal, which the issue itself acknowledges as 'medium confidence'.
Effort	1	The change involves adding detection guidance to a single sub-agent skill definition file (intent-coherence.md) and validating against a test diff. The scope is well-defined and doesn't require architectural changes, but does require understanding the sub-agent's current behavior and crafting nuanced detection heuristics.

Formula: (1.5 x 1.5 x 0.7) / 1 = 1.58