semgrep-review

name	semgrep-review
description	Run a semgrep scan and turn findings into triaged, contextual fixes

Run a static-analysis pass with semgrep and own the findings end to end.

1. Check the tool: semgrep --version. If it's missing, ask for it with request_tool("semgrep", …) rather than skipping the pass. If the user declines, continue with a targeted manual review — read the routes/handlers, the auth and session code, every query built by string concatenation, deserialization, and outbound requests built from user input — and say in your report that the static pass was manual, so the user knows the coverage is narrower than a full scan. Note that community semgrep rules miss whole classes (e.g. SQL built through a project's own DB wrapper), so reading the code is worth doing even when it runs.
2. Scan the repo (from its root): semgrep scan --config auto --json --quiet -o /tmp/semgrep.json Use --config auto unless the repo carries its own rules (.semgrep.yml, semgrep.yml) — prefer the repo's own configuration when present.
3. Parse the JSON and triage EVERY finding — do not echo the raw report:
   • Read the flagged code and enough surrounding context to judge reachability.
   • Is the tainted input attacker-controlled or internal? Is there an upstream guard?
   • Rate: critical / high / medium / low / noise, with a one-line justification each.
4. Fix what's real, highest severity first:
   • Match the codebase's own conventions (its validation helpers, escaping utilities, parameterized-query style) — read neighboring code before writing the fix.
   • Add or extend a test that fails without the fix where the test harness makes that reasonable.
   • Group fixes by theme (one branch per theme), never one giant mixed diff.
5. For findings you judge noise, say WHY (e.g. constant input, dead code, framework already escapes) — never silently drop them, and never add ignore rules to make the scanner quiet without agreement.
6. Deliver: a short findings table (severity · location · verdict · action) and the fix branches/PRs. If the repo has no semgrep config, offer to commit a starter .semgrep.yml pinned to the rulesets that mattered here.