fabro/AGENTS.md

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Build and test commands

Rust

• cargo build --workspace — build all crates
• cargo nextest run --workspace — run all unit tests
• cargo nextest run -p fabro-server — test a single crate
• cargo nextest run -p fabro-workflows -- test_name — run a single test
• set -a && source .env && set +a && cargo nextest run --workspace --profile e2e --run-ignored only — run all E2E live tests (requires credentials in .env, see .env.example)
• set -a && source .env && set +a && cargo nextest run -p fabro-llm --profile e2e --run-ignored only — run E2E tests for a single crate
• cargo fmt --check --all — check formatting
• cargo clippy --workspace -- -D warnings — lint

TypeScript (fabro-web)

• cd apps/fabro-web && bun run dev — start React dev server
• cd apps/fabro-web && bun test — run tests
• cd apps/fabro-web && bun run typecheck — type check
• cd apps/fabro-web && bun run build — production build

Marketing site (apps/marketing)

• cd apps/marketing && bun run dev — start Astro dev server
• cd apps/marketing && bun run build — production build
• cd apps/marketing && bunx vercel --prod — deploy to Vercel (project: website, domain: fabro.sh)

Dev servers

1. fabro serve — starts the Rust API server (demo mode is per-request via X-Fabro-Demo: 1 header)
2. cd apps/fabro-web && bun run dev — starts the React dev server
3. Mintlify docs dev server (requires Docker — mintlify dev needs Node LTS which may not match the host):

   docker run --rm -d -p 3333:3333 -v $(pwd)/docs:/docs -w /docs --name mintlify-dev node:22-slim \
     bash -c "npx mintlify dev --host 0.0.0.0 --port 3333"
   

   Then open http://localhost:3333. Stop with docker stop mintlify-dev.

API workflow

The OpenAPI spec at docs/api-reference/fabro-api.yaml is the source of truth for the fabro-api HTTP interface.

1. Edit docs/api-reference/fabro-api.yaml
2. cargo build -p fabro-api-types — build.rs regenerates Rust types via typify
3. Write/update handler in lib/crates/fabro-server/src/server.rs, add route to build_router()
4. cargo nextest run -p fabro-server — conformance test catches spec/router drift
5. cd lib/packages/fabro-api-client && bun run generate — regenerates TypeScript Axios client

Architecture

Fabro is an AI-powered workflow orchestration platform. Workflows are defined as Graphviz graphs, where each node is a stage (agent, prompt, command, conditional, human, parallel, etc.) executed by the workflow engine.

Rust crates (lib/crates/)

• fabro-cli — CLI entry point. Commands: run, exec, serve, validate, parse, cp, model, doctor, init, install, ps, system prune, llm
• fabro-workflows — Core workflow engine. Parses Graphviz graphs, runs stages, manages checkpoints/resume, hooks, retros, and human-in-the-loop interactions
• fabro-agent — AI coding agent with tool use (Bash, Read, Write, Edit, Glob, Grep, WebFetch). Sandbox trait abstracts execution environments
• fabro-server — Axum HTTP server. Routes for runs, sessions, models, completions, usage. SSE event streaming. Demo mode via header
• fabro-exe — SSH-based sandbox implementation (ExeSandbox)
• fabro-sprites — Sprites VM sandbox implementation via sprite CLI
• fabro-llm — Unified LLM client with providers: Anthropic, OpenAI, Gemini, OpenAI-compatible, plus retry/middleware/streaming
• fabro-api-types — Auto-generated Rust types from OpenAPI spec (build.rs + typify)
• fabro-github — GitHub App auth (JWT signing, installation tokens, PR creation)
• fabro-db — SQLite with WAL mode, schema migrations
• fabro-mcp — Model Context Protocol client/server
• fabro-slack — Slack integration (socket mode, blocks API)
• fabro-devcontainer — Parses .devcontainer/devcontainer.json for container setup
• fabro-git-storage — Git-based storage with branch store and snapshots
• fabro-telemetry — CLI analytics (Segment) and crash reporting (Sentry), with anonymous IDs, command sanitization, and detached subprocess delivery
• fabro-util — Shared utilities (redaction, terminal formatting)

TypeScript (apps/ and lib/packages/)

• apps/fabro-web — React 19 + React Router + Vite + Tailwind CSS frontend
• lib/packages/fabro-api-client — Auto-generated TypeScript Axios client from OpenAPI spec

Key design patterns

• Sandbox trait — Uniform interface for local, Docker, SSH (ExeSandbox), Sprites, and Daytona execution environments
• Graphviz graph workflows — Stages and transitions defined as Graphviz graph attributes
• OpenAPI-first — fabro-api.yaml drives both Rust type generation (typify) and TypeScript client generation (openapi-generator)
• Checkpoint/resume — Workflows can be paused, checkpointed, and resumed

Logging and events

When working on Rust crates, read the relevant strategy doc before making changes:

• files-internal/logging-strategy.md — read when adding tracing calls (info!, debug!, warn!, error!), working on error handling paths, or adding new operations that should be observable
• files-internal/events-strategy.md — read when adding or modifying WorkflowRunEvent variants, touching EventEmitter/emit(), changing progress.jsonl output, or adding new workflow stage types

Shell quoting in sandbox code

When interpolating values into shell command strings (in fabro-exe and fabro-workflows), always use the shell_quote() helper (backed by shlex::try_quote). Never use manual replace('\'', "'\\''") or unquoted interpolation. This applies to file paths, branch names, URLs, env vars, image names, glob patterns, and any other user-controlled input assembled into a shell script.

Rust import style

• Types (structs, enums, traits): import by name — use crate::outcome::Outcome;
• Functions: import the parent module, call as module::function() — use fabro_workflows::operations; operations::create(...)
• No glob imports in production code (use foo::*). Globs are acceptable in test modules and preludes. Enforced by clippy wildcard_imports lint.

Testing workflows

• fabro run <name> — run a workflow by name (resolves fabro/workflows/<name>/workflow.toml), e.g. fabro run repl
• Use --no-retro to skip the retro step and finish faster