The domain_tools.py module#

Summary#

DomainToolSpec

Metadata describing a domain tool to a MCP leaf.

DomainTool

A registered domain tool — spec plus typed async handler.

schema_from_signature

Derive a minimal JSON schema from a typed handler signature.

DomainToolHandler

Description#

Domain-tool registration framework.

A domain tool is one that does pure backend/catalog/Fluent introspection work with no dependency on a plan builder, journal, learned constraints, or recipe registry. Every domain tool lives on an MCP leaf. When an optional higher-level agent layer is installed, it reaches these tools over the MCP wire (an MCP client pool), not by direct Python import. This package never imports that agent layer. The dependency direction is strictly one-way (agent → this package).

The contract is intentionally small so that migrating a handler from the agent layer is a mechanical rewrite. A domain tool is a typed async function with the signature:

async def my_tool_impl(
    backend: Backend,
    *,
    arg1: int,
    arg2: str | None = None,
) -> dict[str, Any]: ...

It is paired with a name, description, and (optional) live-session flag:

DomainTool(
    spec=DomainToolSpec(name="my_tool", description="..."),
    handler=my_tool_impl,
)

The leaf calls FluidsLeafMCP._register_domain_tools() with a list of these. The helper synthesizes a wrapper whose inspect.Signature mirrors the handler minus the backend parameter so FastMCP can extract the JSON input schema from the wrapper. There is no parallel JSON-schema-on-the-spec to keep in sync with the handler signature.

The handler receives the leaf’s active ansys.fluent.mcp.common.backend.Backend plus the validated keyword arguments. There is no loop state, no journal, no plan builder. A tool that needs the plan builder, journal, or recipe registry is agent-only by definition and lives in the optional agent layer instead, not in this package.

Module detail#

domain_tools.schema_from_signature(handler: DomainToolHandler) → dict[str, Any]#

Derive a minimal JSON schema from a typed handler signature.

Drops the leading backend parameter and emits one properties entry per keyword-only argument. The mapping is intentionally small: str -> "string", int -> "integer", float -> "number", bool -> "boolean", dict -> "object", list -> "array" plus None for Optional[...] arms. Anything else falls back to a parameter without a type constraint. The handler is still callable. The schema just documents fewer expectations.

Parameters:
handlerDomainToolHandler

Callable inspected or registered by the helper.

Returns:
dict[str, Any]

Mapping containing the operation result.

domain_tools.DomainToolHandler#