21 Apr 2025 2 min read gpt5

Automating Code Reviews with GPT‑5 & GitHub Actions

Ship better, thrive together—while the bots do the boring bits.

Hook – Why you’ll care (in 60 sec)

Code reviews are the last mile of quality, yet they’re where velocity often screeches to a halt. GPT‑5 can now parse entire pull requests, flag defects, suggest refactors, and even coach on style—all in seconds. Pair it with a lightweight GitHub Action and you free senior devs to focus on architecture, mentoring, and the gnarly edge‑cases only humans can catch.

1. What “AI‑Assisted Review” Really Buys You

Pain Point	Manual Reviews	GPT‑5‑Assisted Reviews
Turn‑around time	Hours—or days during crunch	~60 s end‑to‑end
Reviewer fatigue	High; nit‑picks drain focus	Low; bot handles nits
Consistency	Varies by reviewer	Deterministic prompts
Knowledge sharing	Depends on reviewer mood	Bot leaves inline pedagogy

Bottom line: Automating the first pass catches ≈ 80 % of low‑hanging issues and standardizes feedback so humans can tackle high‑risk logic.

2. Architecture in 60 Seconds

┌───────────┐    push/pull‑request    ┌────────────┐
│ Developer │ ──────────────────────▶ │ GitHub     │
└───────────┘                         │ Action     │
    ▲                                 │ (Docker)   │
    │ review‑comments / status        └────┬───────┘
    │                                      │
    │            prompts + diff            ▼
    │             ┌────────────────────────┐
    └────────────▶│       GPT‑5 API        │
                  └────────────────────────┘

Trigger: pull_request events on open or synchronize
Action job: Runs a slim Docker image that
1. Collects changed files (git diff against base)
2. Splits them into ≤ 100 LOC chunks
3. Crafts system + reviewer prompts (style guide, severity rubric)
4. Streams results back as review comments / a PR status check
Fail‑fast: Critical findings mark the check as failed and block merges; minor items arrive as comments.

3. Quick‑Start Checklist

#	Step	Example
1	Add secret `OPENAI_API_KEY`	Repo → Settings → Secrets
2	Create workflow `.github/workflows/gpt-review.yml`	See YAML below
3	Pull Action image	`ghcr.io/code2culture/gpt5-review:latest`
4	Tune prompts	e.g. `prompt.md` loaded at runtime
5	Pilot on one team	Track false‑positives for a sprint
6	Gate merges	Require the “GPT‑5 Review” check

Minimal gpt-review.yml

name: GPT‑5 Code Review
on:
  pull_request:
    types: [opened, synchronize, reopened]

jobs:
  review:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: GPT‑5 Review
        uses: ghcr.io/code2culture/gpt5-review@v1
        env:
          OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
          MAX_TOKENS: "4096"
          CRIT_THRESHOLD: "0.6"   # blocks merge if higher

One‑Sentence Takeaway

Automating the first pass of every PR with GPT‑5 and GitHub Actions slashes review latency, raises consistency, and lets humans do the thinking work that truly moves the needle.