Error codes

Your tools define their own codes. These are the codes Carmy produces:

Execution

code	category	when
`TOOL_NOT_FOUND`	`not_found`	no tool has this name
`INVALID_ARGUMENTS`	`validation`	the arguments don’t match the input schema
`INVALID_ID`	`validation`	an empty execution ID, or a `request_id` longer than 256 bytes
`CONFIRMATION_REQUIRED`	`permission`	a destructive or confirmation-required tool without `confirm:<tool>`
`FORBIDDEN`	`permission`	`RequireToolPermission` is enabled and `tool:<name>` is missing
`IDEMPOTENCY_CONFLICT`	`conflict`	a `request_id` reused with a different tool or different arguments
`EXECUTION_UNCERTAIN`	`conflict`	a `request_id` whose execution is running or was interrupted
`IDEMPOTENCY_CAPACITY`	`capacity`	the in-memory idempotency store is full
`TIMEOUT`	`timeout`	the deadline passed; external effects may have committed
`CANCELLED`	`cancelled`	the execution was cancelled; external effects may have committed
`TOOL_PANIC`	`internal`	the tool panicked; external effects may have committed
`INVALID_OUTPUT`	`internal`	the output doesn’t match the output schema, or can’t be serialized

HTTP

code	status	when
`INVALID_REQUEST`	400	the body is not a valid execution request; see `details.reason`
`PAYLOAD_TOO_LARGE`	413	the body exceeds 1 MiB

Startup

These are returned by build(), run() and listen() as carmy::Error::Registration:

code	when
`INVALID_TOOL_NAME`	a name is not 1–128 ASCII letters, digits, `_`, `-` or `.`
`DUPLICATE_TOOL`	two tools share a name
`INVALID_SCHEMA`	an input or output schema is not a valid JSON Schema
`MISSING_STATE`	a tool needs a `State<T>` that was never registered