agentic-dev-loop

agentic-dev-loop

Turn an LLM into a gated, sandboxed, resumable construction loop over your codebase.

Describe your pipeline in one YAML file — agent steps, mechanical test gates, and trusted actions — and agentic-dev-loop runs it end to end: agent and command steps get kernel-level sandboxing via Docker, verdicts route the graph, every boundary is checkpointed, and nothing gets committed until every gate passes.

flowchart LR
    dev["agent: dev"] --> test{{"test gate"}} --> review["agent: review"] --> qa["agent: qa"] --> commit["action: commit"]
    test -- fail --> dev
    review -- fail --> dev
    qa -- fail --> dev

• A tool, not a wiring project. One CLI entry point, opinionated defaults, fixed safety policies. You write the pipeline and the agent definitions — nothing else.
• Deterministic. Same pipeline + same state → same routing. Verdicts are parsed from files, retries are bounded, nothing is best-effort.
• Sandboxed by default. The agent's shell and every command step run inside an always-on Docker sandbox. There is no opt-out.

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Core features

The fixed policies are the product: fail fast on missing config/secrets, no silent fallbacks, verdicts only from artifacts, bounded retries, per-attempt artifact hygiene, a single clean-worktree-gated commit point, and no default LLM timeout (agent runs are long).

Installation

Prerequisites

pip install agentic-dev-loop==1.0.0a3   # pin the current alpha release explicitly
agentic-dev-loop --version

On the first run the engine pulls the digest-pinned dev image (ghcr.io/lukedawilson/agentic-dev-loop/dev) and verifies its digest — the supply-chain check refuses to continue on a mismatch. If you're running pre-publish tooling, point AGENTIC_DEV_LOOP_DEV_IMAGE at your locally built image. Engine setup, first-run details, the full pipeline.yaml contract, and troubleshooting for every fail-fast code live in docs/setup.md.

Usage

export OPENAI_API_KEY=...                          # whatever api_key_env names
agentic-dev-loop pipeline.yaml                     # run it
agentic-dev-loop pipeline.yaml --dry-run           # validate first — no LLM, no Docker
agentic-dev-loop pipeline.yaml --resume <thread-id> --max-attempts 5

Exit code is 0 on pipeline success, 1 otherwise.

What a run looks like (the shipped self-loop example):

1. dev — the dev agent works with full context (loaded docs + shared files). Its edits are untracked; only declared produces: files are hygiene-tracked.
2. test — a mechanical command step runs the suite inside the sandbox. Exit 0 moves on; anything else rewinds to dev with the failing output.
3. review / qa — verdict agents write artifacts whose VERDICT: lines route the graph. fail rewinds to dev and consumes an attempt.
4. commit — the single commit point fires only when all gates passed and the worktree was clean at start.
5. success — committed; or failure when attempts are exhausted.

pipeline.yaml reference

name: my-construction-loop
extensions:
  - agentic_dev_loop.extensions.aidlc:AidlcExtension   # bundled AI-DLC doc loader
additional_files:
  - ../README.md                                       # shared context for every agent step

llm:
  model: openai/deepseek-v4-pro
  base_url: https://api.deepseek.com
  api_key_env: OPENAI_API_KEY

max_attempts: 10                                        # CLI --max-attempts overrides
agents_dir: sdk_agents                                  # your <name>.agent.md files

steps:
  - name: dev
    agent: dev
    produces: implementation-summary.md
    on_pass: test

  - name: test
    command: .venv-sandbox/bin/python -m pytest tests/ -q -m "not docker"
    setup: python -m venv .venv-sandbox && .venv-sandbox/bin/pip install -e ".[dev]"
    timeout: 600
    on_pass: review
    on_fail: { goto: dev, retry: true }

  - name: review
    agent: review
    artifact: review-findings.md
    verdicts: { pass: APPROVED, fail: NEEDS CHANGES }
    on_pass: qa
    on_fail: { goto: dev, retry: true }

  - name: qa
    agent: qa
    artifact: qa-report.md
    verdicts: { pass: PASS, fail: FAIL }
    on_pass: commit
    on_fail: { goto: dev, retry: true }

  - name: commit
    action: commit
    params: { message: "feat: construct {subject} (agent dev loop)" }

Per-stage networking

The sandbox is network-off by default. A step that legitimately needs egress — a QA step that curls a service it booted, an agent that must hit an API or fetch package metadata mid-conversation — declares it explicitly:

steps:
  - name: fetch-docs
    command: curl -fsSL https://example.com/spec.json -o spec.json
    network: true            # egress for this step only

• Default off. Every step runs with --network none unless it declares network: true. A networked step runs in a second, otherwise-identical sandbox container (--read-only, --cap-drop ALL, single workspace mount) on the Docker bridge network — the default network-none container is always created too, so no infrastructure work happens mid-run.
• Command and agent steps may declare it. Action steps are host-side and never take it (a load-time error).
• Author opt-in is the control. A networked step gives its agent raw egress for that stage; the default stays network-off everywhere. Reserve it for stages that need it (QA, integration). The residual risk is documented in docs/setup.md.

Development environment

git clone git@github.com:lukedawilson/agentic-dev-loop.git
cd agentic-dev-loop
./setup-venv.sh                       # idempotent .venv setup (never touches bare pip)
# create .env with your LLM key (loaded by trigger-agentic-dev-loop.sh, never committed):
#   echo 'OPENAI_API_KEY=...' > .env
python -m pytest tests/ -q            # fast suite
python -m pytest tests/ -q -m "not docker"   # skip engine-dependent tests
./trigger-agentic-dev-loop.sh --dry-run      # run the shipped pipeline against this repo
./run-demo.sh                         # viz demo — scripted run replay, no pipeline needed

• setup-venv.sh is safe to re-run and picks the right interpreter even on machines with exotic Python installations.
• Docker-marked integration tests need a local daemon; CI runs them on Linux.
• The shipped pipeline (agentic-dev-loop/pipeline.yaml) dogfoods the tool on its own repo — dev → test → review → qa → commit, with the engine's own three agent definitions in sdk_agents/.
• CI: ci.yml (unit + integration suite, ubuntu + windows), publish-image.yml (multi-arch dev image, amd64 + arm64), release.yml (PyPI publishing).

Contributing

• Read AGENTS.md first — it is the instruction set for both human and agent contributors (default mode: the user drives, ask before coding, TDD, no silent fallbacks).
• Development is structured by AI-DLC — the lifecycle workflow in .aidlc/aidlc-rules/aws-aidlc-rules/ with working docs (plans, units, state) in aidlc-docs/. The bundled document loader autodetects the current unit from aidlc-state.md via --aidlc-unit, or load any plan with --plan.
• OpenCode commands over the workflow: /unit-status, /epic-status, /ticket-details, /update-subtask, /apply-aidlc-patches, and more.
• Working extension samples (actions, tools, document loaders) ship as tests/sample_ext.py.

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