Your API. One policy. Every agent interface.

Try the behavior before the architecture

The payments fixture includes a refund operation with explicit confirmation and idempotency requirements. Compile it, omit those requirements, and inspect the refusal. Supply them and inspect the redacted request plan. Both paths work without credentials or an upstream payment service.

After installing from source:

pnpm anvil compile examples/payments/openapi.yaml \
  --manifest examples/payments/anvil.yaml \
  --service payments --out generated/payments
pnpm anvil status generated/payments
pnpm anvil inspect generated/payments

Run the full local quickstart to exercise the policy and test the generated MCP server against a mock.

What you can use afterward

Output	Consumer	Shared contract
Typed CLI	Developer or coding harness	Approved operations and validated arguments
MCP server	MCP client	The same operation and runtime policy
Four client SDKs	TypeScript, Python, Go, Java application	Generated operation methods and gates
Skill and hooks	Coding harness	Operation guidance and supported early refusals
Mocks and assurance records	CI or reviewer	Executable checks tied to the bundle hash
Deployment inputs	Operator	Configuration and release plans

The CLI and MCP runtime require installed or linked Anvil packages. The SDK trees can be vendored independently. SDK details.

Start from the material you have

Input	First step	What it produces
API description	anvil agentify	Candidate bundle, assessment, and capability proposals
Gateway export	anvil estate inventory	Gateway-aware inventory with provenance
Legacy deployment configuration	anvil legacy inventory	Offline evidence and technical candidates
Existing MCP server	anvil adopt	Review artifacts and an adoption plan

agentify stops for review. It does not infer approval or deploy. Legacy inventory does not generate or run a bridge. Parser support also differs from wire support: native gRPC requires a JSON transcoder; unsupported streaming and SOAP bindings are refused. Source support.

The model prevents interfaces from disagreeing

AIR, the Anvil Intermediate Representation, records schema, effect, risk, authentication, approval, confirmation, idempotency, retry, and evidence requirements. Every generated surface reads that model.

Condition	Result
Operation is unapproved	It is absent from callable surfaces
Required confirmation is missing	The call fails before execution
Idempotency is unproven	Automatic mutation retry is disabled
A harness hook is absent	Runtime policy still applies
Bundle bytes change	Previous assurance evidence becomes stale
publish succeeds	An operator plan exists; deployment has not occurred

The compiler cannot recover a missing business guarantee from an HTTP method. Supply supported semantics in the reviewed manifest.

Pick the next step

Goal	Guide
Compile and exercise one bundle locally	Quickstart
Resolve uncertain operations	Enrich and approve
Process a gateway export	Gateway import
Inventory middleware without an API description	Legacy inventory
Require fresh evidence before release	CI integration
Understand a refusal or incomplete bundle	Troubleshooting

Anvil is a source-installed toolchain for reviewed integrations. A small, single-client API wrapper may require less setup. Its value grows when several interfaces must preserve the same operation semantics.