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

Adds substantial context beyond annotations: annotations only say readOnly=false, destructive=false, idempotent=false, while the description discloses the 403 rights-grant refusal and the confirm requirement, and the schema notes quota consumption. It does not say whether the call is synchronous or returns a job id for clipwright_job_status to poll, which is the main remaining gap.

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?

Three short sentences with zero filler, and the core capability is stated first, followed by the two hard preconditions. Nothing is repeated from the schema and nothing is wasted.

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?

For a non-idempotent write tool with four parameters, no output schema, and only 25% schema coverage, the description leaves too much open: it does not cover source/grant_id/top_n semantics, nor does it explain what the caller gets back or how to track progress. The preconditions are well covered, but the parameter and return surface are not.

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 coverage is only 25% — just 'confirm' is documented, and that documentation lives in the schema rather than the description. The description never explains what 'source' accepts (path, URL, id), what grant_id should contain, or what top_n limits, so three of four parameters are semantically undocumented everywhere.

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?

Names a specific verb and output ('Create vertical 9:16 captioned clips from a source'), which is far more informative than the tool name alone and distinguishes it from siblings like clipwright_job_status or clipwright_register_grant. It does not explicitly contrast with those siblings, but the resource and format are unambiguous.

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?

Gives real preconditions: a rights grant must cover the source or the call is refused with 403, and confirm=true is mandatory. What is missing is any explicit routing, e.g. pointing to clipwright_check_rights or clipwright_register_grant when no grant exists, so the agent must infer the correct preceding step.

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