Function _walk_schema_positions

src/mcp/shared/inbound.py:114–140

Yield `(properties_path, schema)` for every schema position in `root`. `properties_path` is the chain of `properties` keys from the root to the position, or `None` once any other applicator keyword has been crossed. The root itself yields `()`. Only the JSON Schema 2020-12 applicators

(root: Any)

def _walk_schema_positions(root: Any) -> Iterator[tuple[tuple[str, ...] | None, dict[str, Any]]]:
    """Yield `(properties_path, schema)` for every schema position in `root`.

    `properties_path` is the chain of `properties` keys from the root to the
    position, or `None` once any other applicator keyword has been crossed.
    The root itself yields `()`. Only the JSON Schema 2020-12 applicators
    listed above are entered; instance-data keywords are not, and `$ref` is
    not dereferenced, so the walk terminates on any finite JSON value. An
    explicit stack keeps the function total even on pathologically deep input.
    """
    stack: list[tuple[tuple[str, ...] | None, Any]] = [((), root)]
    while stack:
        path, node = stack.pop()
        if not isinstance(node, dict):
            continue
        schema = cast(dict[str, Any], node)
        yield path, schema
        for kw, val in schema.items():
            if kw == "properties" and isinstance(val, dict):
                for name, sub in cast(dict[str, Any], val).items():
                    stack.append(((*path, name) if path is not None else None, sub))
            elif kw in _SUBSCHEMA_SINGLE:
                stack.append((None, val))
            elif kw in _SUBSCHEMA_LIST and isinstance(val, list):
                stack.extend((None, sub) for sub in cast(list[Any], val))
            elif kw in _SUBSCHEMA_MAP and isinstance(val, dict):
                stack.extend((None, sub) for sub in cast(dict[str, Any], val).values())


def encode_header_value(value: str) -> str: