Marcos
8c491a7626
The reviewer runs an opencode agent with `bash: "*": allow` over a checkout of the PR author's branch, and the pod holds a Gitea Write credential. Those two facts had no wall between them. Security - _build_env now allow-lists the subprocess environment instead of inheriting it, so PRAGENT_BOT_TOKEN and WEBHOOK_SECRET never reach the agent. This was the live hole: a PR body or an AGENTS.md could ask the agent to `curl` the token out, and it had both the value and the tool. - sanitize_workdir deletes author-controlled agent-instruction files from the checkout before opencode starts (AGENTS.md at any depth, CLAUDE.md, .cursorrules, a repo opencode.json/.opencode, copilot-instructions.md). opencode loads nested AGENTS.md as instructions, so a PR could otherwise ship its own system prompt. They are still reviewed, as data. - The brief fences PR title/body and diff in --- UNTRUSTED --- markers under a trust-boundary preamble; the pragent agent, the three lens subagents and the review-methodology skill now treat injection attempts as a critical finding to report rather than an instruction to obey. - .pr-review.json is read from the PR's base branch, not the head sha. Its `instructions` field is spliced into the reviewer's prompt, so head-ref reading let any author rewrite the reviewer's rules. Fields are length-capped. - Untar rejects escaping symlinks, parent traversal, and writes through a planted symlink (tar-slip). - The image runs as uid 10001 instead of root. Robustness - Bounded review concurrency (PRAGENT_MAX_CONCURRENT_REVIEWS, default 2). Each review forks an opencode process; a thread per delivery was a fork bomb on a burst of labels or Gitea retries. - An in-flight (repo, index, sha) claim closes the check-then-act race in the sha-marker dedupe, where two deliveries a second apart both read "not yet reviewed" and both posted. - Request bodies are capped before being read into memory. Correctness - parse_diff_anchors counts a whitespace-stripped blank context line. Skipping it desynced the new-line counter for the rest of the hunk and silently misplaced every later inline comment in that file. - post_inline_review's body-only fallback folds the anchored findings into the body. It previously posted a summary saying "N inline comment(s) below" with no comments and no findings — losing them all on the one path that matters. - fetch_pr_diff's files-endpoint fallback emits real a// b/ prefixes (so changed_files and the anchor parser work on it) and reports both HTTP statuses in its error instead of the same one twice. - The CI workflow template pins PRAGENT_ENGINE=ollama; review_pr defaults to opencode, which does not exist on a Gitea Actions runner. Tests: 68 -> 101, covering each of the above. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01B11e8TZZxJyzHW7jj7KWUN
pragent
An extensible, forge-agnostic PR review framework. Not a product — a toolkit that teams extend with their own review dimensions.
Status: design approved; framework build deferred. A pilot is live on
glm-5.2:cloud with two delivery paths:
- Central webhook service (preferred, least per-repo setup): a Gitea
user-level webhook posts PR events to an always-on in-cluster service that
gates on the
AI-REVIEWlabel. Onboarding a repo = addpragent-botcollaborator + create the label + label a PR. Seepilot/README-webhook.md. - CI-step (legacy): a per-repo Gitea Action fetches the reviewer script at
runtime. See
pilot/README.md.
The framework design remains at
docs/plans/2026-08-04-pragent-design.md;
the pilot is its bootstrap and will be superseded by pragent review when the
framework build resumes.
What it is
pragent runs as a CI step. It reads a pull request, decides how much attention the
change deserves, runs the analyzers that apply, and posts ranked findings back to the
forge.
pragent init # one-time repo scan → .pragent/profile.yml (committed, reviewable)
pragent review # the CI step: tier → analyze → aggregate → publish
pragent explain # why did this PR get this tier / these findings?
pragent replay # re-run a past PR against a new prompt or model (the eval loop)
pragent doctor # config, credentials, and adapter health
Why not CodeRabbit / Greptile / Qodo
Those are good products with fixed review dimensions and per-seat pricing. pragent
targets the case where a platform team needs to add its own dimensions — an internal
compliance rule, a service-catalog ownership check, a house performance idiom — without
forking a vendor's reviewer. Cost lands in the same range (~$25/dev/month at 350 PRs/mo
for 20 devs), but the analyzers, the data, and the analytics are yours.
Attention tiers
Every PR is classified before any expensive work happens. Deterministic rules decide first; an ambiguous case gets one cheap model call as tie-breaker.
| Tier | What it means | Cost/PR |
|---|---|---|
trivial |
lockfile bumps, generated code, docs typos | ~$0.005 |
lite |
small change, no risk paths | ~$0.08 |
full |
the default for real changes | ~$0.80–2.00 |
oversized |
too big to review whole; structural summary + deep pass on the hot subset | ~$5 ceiling |
Every tier decision records why, so a surprising outcome is explainable rather than mysterious.
Extension points
Five, all documented in the design doc. Teams override or add; nobody forks.
- Analyzers — drop a YAML + prompt in
.pragent/analyzers/, or install from npm - Forge adapters — Gitea, GitLab, GitHub, local diff
- Tier policy — thresholds and the path risk map, per repo or per org
- Profile enrichers — extend what
pragent initlearns about a repo - Emitter sinks — JSONL by default, OpenTelemetry, or your own
Org config can lock keys, so a repo cannot quietly disable the security analyzer.
Design principles
- Polyglot by construction. Language knowledge lives in the repo profile, not in the reviewer. A new language is a profile change, not a core change.
- One shared prompt prefix. All analyzers for a PR share a byte-identical cached prefix. This is what makes fan-out affordable; it is enforced, not hoped for.
- Everything is traceable. Tier reasons, token counts, cost, latency, and finding outcomes are recorded per run. False-positive rate is measurable per analyzer.
- Fail open. A budget ceiling or an analyzer crash yields a partial review with a clear note, never a blocked pipeline with no explanation.
- The reviewed code is untrusted input. The reviewer runs an agent over a
branch anyone with PR access can write. So it holds no credentials in its
environment, the checkout is stripped of files an agent runtime would load as
instructions, PR-authored text is fenced as data, and reviewer config is read
from the base branch. See "Threat model" in
pilot/README-webhook.md.
Stack
TypeScript + Node, built on the pi agent SDK.
Shipped as an npm package and an OCI image, so CI runners need no local Node install.
Roadmap
- Walking skeleton — local diff, one analyzer, rules-only tiering
- Gitea end to end — adapter, Woodpecker step, PR comments, status checks
- Profile + full tier —
pragent init, shared-prefix caching, analyzer fan-out - Extensibility hardening — plugin loading, config layering,
explain/replay - Second forge — GitLab adapter, Jenkins recipe
- Analytics maturity — OTel export, feedback loop, eval harness
License
TBD.