Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare idempotentHint=true, destructiveHint=false, readOnlyHint=false and openWorldHint=true, so the safety profile is largely covered. The description adds genuinely new context beyond those: full-configuration replacement semantics, an optional API key path (x-api-key header), and the 'Free call' cost signal. There is a mild tension between 'Replaces the full configuration' and destructiveHint=false, but that is consistent with PUT-style idempotent overwrite rather than a true annotation contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two dense sentences, front-loaded with the action and endpoint, then the required/optional body and replacement caveat. No filler or repetition of the title.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The tool ships an output schema, so return values need not be explained, and annotations cover the safety profile. The description supplies the remaining agent-critical facts: full replacement semantics, the HTTP path, API-key optionality, and the free-call cost signal.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents every parameter including enums, defaults, and the Agent-mode/json-excel constraint. The description's parameter list (name, type, schema_definition as required; Agent mode, window_context, source verification as optional) merely restates the schema, adding no format or syntax detail, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource ('Update a Claix schema') and pins it to the concrete endpoint (PUT /api/update-schema/{schema_id}), which cleanly separates it from claix.schemas.create/delete/get/list. It does not explicitly name those siblings, but the verb and endpoint leave no ambiguity about what the tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

'Same body as create' and 'Replaces the full configuration' imply how and when to call it (full replacement rather than a partial patch), which is meaningful guidance. However, there is no explicit when-to-use versus claix.schemas.create or delete, and no stated prerequisites beyond the replacement note.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.