| name | codehub-pr-review |
| description | Use when the user wants to review a pull request, understand what a PR changes, assess risk of merging, or check missing test coverage. Examples: "Review this PR", "What does PR #42 change?", "Is this PR safe to merge?", "Audit the dependencies in this PR". |
PR Review with OpenCodeHub
When to Use
- "Review this PR."
- "What does PR #42 change?"
- "Is this safe to merge?"
- "What's the blast radius of this PR?"
- "Are there missing tests for this PR?"
- "Did this PR introduce a copyleft / unknown license?"
- Reviewing someone else's code changes before merge.
The Golden Workflow
1. mcp__codehub__verdict({ base, head }) → 5-tier merge decision
2. mcp__codehub__list_findings_delta({ base }) → New / fixed / unchanged / updated findings
3. mcp__codehub__detect_changes({ scope: "compare", base_ref }) → Changed symbols + affected flows
4. For each non-trivial changed symbol:
mcp__codehub__impact({ name, direction: "upstream" }) → Blast radius + confidenceBreakdown
5. mcp__codehub__license_audit → Copyleft / unknown / proprietary tiers
6. mcp__codehub__scan (opt-in) → Fresh scanner run — spawns processes
7. Write the review using the output template below
If the context envelope warns the index is stale, run codehub analyze before starting — stale graphs produce stale verdicts.
Checklist
- [ ] Fetch the PR diff (gh pr diff <n> or git diff <base>...<head>)
- [ ] mcp__codehub__verdict — start here; it aggregates the review signal
- [ ] Capture the verdict tier, top drivers, and blockers
- [ ] mcp__codehub__list_findings_delta — new findings since the baseline
- [ ] mcp__codehub__detect_changes — map the diff to affected processes
- [ ] mcp__codehub__impact on each non-trivial changed symbol
- [ ] Inspect confidenceBreakdown per impact — prefer confirmed edges for breakage claims
- [ ] mcp__codehub__license_audit — flag copyleft or unknown license changes
- [ ] (optional) mcp__codehub__scan to re-run scanners if the baseline is stale
- [ ] Write the review in the output template below
Tools
mcp__codehub__verdict — the starting point
mcp__codehub__verdict({ base: "main", head: "HEAD", repo: "my-app" })
→ tier: "auto_merge" | "single_review" | "dual_review" | "expert_review" | "block"
→ drivers: [{ signal, weight, evidence }] // top reasons the tier was chosen
→ blockers: [...] // non-empty only for tier=block
→ next_action: "merge" | "request review from X" | "add tests for Y" | "fix finding Z"
→ exit_code: 0 | 1 | 2
Always lead your review with the tier. If it is block, do not recommend merge. If it is auto_merge, the rest of the review is confirmation, not discovery.
mcp__codehub__list_findings_delta — what changed since baseline
mcp__codehub__list_findings_delta({
repo: "my-app",
base: "main" // compare current scan output to the baseline frozen at base
})
→ new: [{rule, severity, file, line, message}] // introduced by this PR — the scariest bucket
→ fixed: [...] // removed by this PR — give credit
→ unchanged: [...] // still present, not touched
→ updated: [...] // same rule hit at a shifted location
The new bucket is the first thing to surface — it is the PR author's new debt.
mcp__codehub__detect_changes — diff → flows
mcp__codehub__detect_changes({ scope: "compare", base_ref: "main", repo: "my-app" })
→ changed_symbols: [{uid, name, kind, filePath, change}]
→ affected_processes: [CheckoutFlow, RefundFlow]
→ risk_level: LOW | MEDIUM | HIGH | CRITICAL
mcp__codehub__impact — blast radius per changed symbol
mcp__codehub__impact({
name: "validatePayment",
direction: "upstream",
depth: 2,
repo: "my-app"
})
→ byDepth.d1: processCheckout, webhookHandler // WILL BREAK if signature changed
→ byDepth.d2: checkoutRouter // LIKELY AFFECTED
→ affected_processes: [CheckoutFlow]
→ confidenceBreakdown: {confirmed, heuristic, unknown}
→ risk: MEDIUM
If any d=1 caller is NOT in the PR diff, flag it as a potential breakage in your review.
mcp__codehub__license_audit — dependency license tiers
mcp__codehub__license_audit({ repo: "my-app" })
→ by_tier: {
copyleft: [{ name, ecosystem, version, license, manifest }],
unknown: [...],
proprietary: [...],
permissive: [...]
}
→ warnings: [...] // e.g. "package `foo` has no license field in manifest"
If the PR diff touches package.json, pyproject.toml, go.mod, or Cargo.toml, run this and compare tiers against the pre-PR baseline. A new copyleft or unknown entry is a review finding.
mcp__codehub__scan — re-run scanners
Only run this when the baseline is obviously stale. scan has openWorldHint: true and spawns child processes, so use it deliberately.
mcp__codehub__scan({ repo: "my-app" })
mcp__codehub__risk_trends — context on the area being changed
mcp__codehub__risk_trends({ repo: "my-app" })
→ communities: [{ name, risk_score, trend, projection_30d }]
Useful when a PR lands inside a community whose risk is already trending up — call that out in the review.
mcp__codehub__owners — who should review?
mcp__codehub__owners({ repo: "my-app", path: "src/payments" })
→ [{ owner, source: "codeowners" | "git-blame", files, recent_edits }]
Review Dimensions
| Dimension | OpenCodeHub surface |
|---|
| Correctness | context shows callers — are they all compatible with the change? |
| Blast radius | impact.byDepth — anything at d=1 not in the diff is a potential miss |
| Completeness | detect_changes.affected_processes — are they all handled? |
| Confidence | confidenceBreakdown.confirmed vs heuristic — LSP-backed claims win |
| Net new bugs | list_findings_delta.new — introduced by this PR |
| Tests | impact filtered to kind = 'Function' inside test files |
| License hygiene | license_audit before/after diff |
| Ownership | owners — right reviewers requested? |
| Trend | risk_trends — is this area already hot? |
Risk Tier Guide
| Signal | Risk |
|---|
| < 3 symbols touched, 0–1 processes, no new findings | LOW |
| 3–10 symbols, 2–5 processes, ≤ 1 new finding | MEDIUM |
| > 10 symbols OR many processes OR several new findings | HIGH |
| Touches auth, payments, data integrity, or new copyleft | CRITICAL |
| d=1 callers exist outside the PR diff | Flag it |
Example: "Review PR #42"
1. gh pr diff 42 > /tmp/pr42.diff
→ 4 files changed: payments.ts, checkout.ts, types.ts, utils.ts
2. mcp__codehub__verdict({ base: "main", head: "HEAD", repo: "my-app" })
→ tier: "dual_review"
→ drivers: [
{signal: "high-impact symbol changed", weight: 0.4, evidence: "validatePayment"},
{signal: "new scanner finding", weight: 0.3, evidence: "security/no-eval"},
{signal: "missing test coverage on CheckoutFlow", weight: 0.3}
]
→ next_action: "request review from @payments-team"
3. mcp__codehub__list_findings_delta({ repo: "my-app", base: "main" })
→ new: [{rule: "security/no-eval", severity: "error", file: "src/utils/format.ts", line: 44}]
→ fixed: []
4. mcp__codehub__detect_changes({ scope: "compare", base_ref: "main", repo: "my-app" })
→ changed_symbols: [validatePayment, PaymentInput, formatAmount]
→ affected_processes: [CheckoutFlow, RefundFlow]
→ risk_level: MEDIUM
5. mcp__codehub__impact({ name: "validatePayment", direction: "upstream", repo: "my-app" })
→ byDepth.d1: processCheckout, webhookHandler
→ webhookHandler is NOT in the PR diff — flag as potential breakage.
→ confidenceBreakdown: {confirmed: 2, heuristic: 0, unknown: 0}
6. mcp__codehub__impact({ name: "PaymentInput", direction: "upstream", repo: "my-app" })
→ byDepth.d1: validatePayment (in PR), createPayment (NOT in PR)
→ createPayment uses the old PaymentInput shape — breaking change.
7. mcp__codehub__license_audit({ repo: "my-app" })
→ No tier changes vs. main — clean.
8. Compose the review (template below).
Review Output Template
## PR Review: <title>
**Tier: dual_review** **Risk: MEDIUM**
### Verdict drivers
- validatePayment blast radius crosses the PR boundary
- 1 new scanner finding: security/no-eval at src/utils/format.ts:44
- CheckoutFlow has no test coverage for the new branch
### Changes
- 3 symbols changed across 4 files
- 2 execution flows affected: CheckoutFlow, RefundFlow
### Findings
1. **[blocker]** `webhookHandler` (src/webhooks.ts:15) calls `validatePayment`
but is NOT updated in this PR. New signature will throw at runtime.
2. **[blocker]** `createPayment` (src/payments/create.ts:22) uses the old
`PaymentInput` shape. This change is breaking.
3. **[error]** New scanner finding: security/no-eval at src/utils/format.ts:44.
`eval(userInput)` is unsafe.
4. **[ok]** `formatAmount` added optional param — backwards compatible.
### Missing coverage
- CheckoutFlow has no integration test for the new branch.
- No webhook test exercises validatePayment.
### Recommendation
REQUEST CHANGES — resolve the three blockers and add a CheckoutFlow
integration test before re-review.
