Instructions

ACP v1 Baseline

v1 is ACP-native.
/v1/* is removed and returns 410 Gone (application/problem+json).
/opencode/* is disabled during ACP core phases and returns 503.
Prompt/session traffic is ACP JSON-RPC over streamable HTTP on /v1/rpc:
- POST /v1/rpc
- GET /v1/rpc (SSE)
- DELETE /v1/rpc
Control-plane endpoints:
- GET /v1/health
- GET /v1/agents
- POST /v1/agents/{agent}/install
Binary filesystem transfer endpoints (intentionally HTTP, not ACP extension methods):
- GET /v1/fs/file
- PUT /v1/fs/file
- POST /v1/fs/upload-batch
Sandbox Agent ACP extension method naming:
- Custom ACP methods use _sandboxagent/... (not _sandboxagent/v1/...).
- Session detach method is _sandboxagent/session/detach.

ACP is the primary protocol for agent/session behavior and all functionality that talks directly to the agent.
ACP extensions may be used for gaps (for example skills, models, and related metadata), but the default is that agent-facing behavior is implemented by the agent through ACP.
Custom HTTP APIs are for non-agent/session platform services (for example filesystem, terminals, and other host/runtime capabilities).
Filesystem and terminal APIs remain Sandbox Agent-specific HTTP contracts and are not ACP.
Keep GET /v1/fs/file, PUT /v1/fs/file, and POST /v1/fs/upload-batch on HTTP:
- These are Sandbox Agent host/runtime operations with cross-agent-consistent behavior.
- They may involve very large binary transfers that ACP JSON-RPC envelopes are not suited to stream.
- This is intentionally separate from ACP native fs/read_text_file and fs/write_text_file.
- ACP extension variants may exist in parallel, but SDK defaults should prefer HTTP for these binary transfer operations.

This repository/product is Sandbox Agent.
Gigacode is a separate user-facing UI/client, not the server product name.
Gigacode integrates with Sandbox Agent via the OpenCode-compatible surface (/opencode/*) when that compatibility layer is enabled.
Canonical extension namespace/domain string is sandboxagent.dev (no hyphen).
Canonical custom ACP extension method prefix is _sandboxagent/... (no hyphen).

HTTP contract and problem/error mapping: server/packages/sandbox-agent/src/router.rs
ACP client runtime and agent process bridge: server/packages/sandbox-agent/src/acp_runtime/mod.rs
Agent/native + ACP agent process install and lazy install: server/packages/agent-management/
Inspector UI served at /ui/ and bound to ACP over HTTP from frontend/packages/inspector/

TypeScript clients are split into:
- acp-http-client: protocol-pure ACP-over-HTTP (/v1/acp) with no Sandbox-specific HTTP helpers.
- sandbox-agent: SandboxAgent SDK wrapper that combines ACP session operations with Sandbox control-plane and filesystem helpers.
SandboxAgent entry points are SandboxAgent.connect(...) and SandboxAgent.start(...).
Stable Sandbox session methods are createSession, resumeSession, resumeOrCreateSession, destroySession, sendSessionMethod, onSessionEvent, setSessionMode, setSessionModel, setSessionThoughtLevel, setSessionConfigOption, getSessionConfigOptions, and getSessionModes.
Session helpers are prompt(...), send(...), onEvent(...), setMode(...), setModel(...), setThoughtLevel(...), setConfigOption(...), getConfigOptions(), and getModes().
Cleanup is sdk.dispose().

For TypeScript docs/examples, source of truth is implementation in:
- sdks/typescript/src/client.ts
- sdks/typescript/src/index.ts
- sdks/acp-http-client/src/index.ts
Do not document TypeScript APIs unless they are exported and implemented in those files.
For HTTP/CLI docs/examples, source of truth is:
- server/packages/sandbox-agent/src/router.rs
- server/packages/sandbox-agent/src/cli.rs
Keep docs aligned to implemented endpoints/commands only (for example ACP under /v1/acp, not legacy /v1/sessions APIs).

Keep CLI subcommands and HTTP endpoints in sync.
Update docs/cli.mdx when CLI behavior changes.
Regenerate docs/openapi.json when HTTP contracts change.
Keep docs/inspector.mdx and docs/sdks/typescript.mdx aligned with implementation.
Append blockers/decisions to research/acp/friction.md during ACP work.
docs/agent-capabilities.mdx lists models/modes/thought levels per agent. Update it when adding a new agent or changing fallback_config_options. If its "Last updated" date is >2 weeks old, re-run cd scripts/agent-configs && npx tsx dump.ts and update the doc to match. Source data: scripts/agent-configs/resources/*.json and hardcoded entries in server/packages/sandbox-agent/src/router/support.rs (fallback_config_options).
Some agent models are gated by subscription (e.g. Claude opus). The live report only shows models available to the current credentials. The static doc and JSON resource files should list all known models regardless of subscription tier.
TypeScript SDK tests should run against a real running server/runtime over real /v1 HTTP APIs, typically using the real mock agent for deterministic behavior.
Do not use Vitest fetch/transport mocks to simulate server functionality in TypeScript SDK tests.

When manually testing bleeding-edge (unreleased) versions of sandbox-agent in examples/, use SANDBOX_AGENT_DEV=1 with the Docker-based examples.
This triggers examples/shared/Dockerfile.dev which builds the server binary from local source and packages it into the Docker image.
Example: SANDBOX_AGENT_DEV=1 pnpm --filter @sandbox-agent/example-mcp start

Docker-backed Rust and TypeScript tests build docker/test-agent/Dockerfile directly in-process and cache the image tag only in memory (OnceLock in Rust, module-level variable in TypeScript).
Do not add cross-process image-build scripts unless there is a concrete need for them.

Channel policy:
- Sandbox Agent install/version references use a pinned minor channel 0.N.x (for curl URLs and sandbox-agent / @sandbox-agent/cli npm/bun installs).
- Gigacode install/version references use latest (for @sandbox-agent/gigacode install/run commands and gigacode-install.* release promotion).
- Release promotion policy: latest releases must still update latest; when a release is latest, Sandbox Agent must also be promoted to the matching minor channel 0.N.x.
Keep every install-version reference below in sync whenever versions/channels change:
- README.md
- docs/acp-http-client.mdx
- docs/cli.mdx
- docs/quickstart.mdx
- docs/sdk-overview.mdx
- docs/react-components.mdx
- docs/session-persistence.mdx
- docs/deploy/local.mdx
- docs/deploy/cloudflare.mdx
- docs/deploy/vercel.mdx
- docs/deploy/daytona.mdx
- docs/deploy/e2b.mdx
- docs/deploy/docker.mdx
- frontend/packages/website/src/components/GetStarted.tsx
- .claude/commands/post-release-testing.md
- examples/cloudflare/Dockerfile
- examples/daytona/src/index.ts
- examples/daytona/src/daytona-with-snapshot.ts
- examples/docker/src/index.ts
- examples/e2b/src/index.ts
- examples/vercel/src/index.ts
- scripts/release/main.ts
- scripts/release/promote-artifacts.ts
- scripts/release/sdk.ts
- scripts/sandbox-testing/test-sandbox.ts