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

Annotations already cover readOnlyHint, so the bar is lower, yet the description adds real context: the operation is free (no cost incurred), internal jobs return a studio_internal_job marker, and the result must be fetched elsewhere. It still doesn't say whether a given status is terminal or whether polling is rate-limited.

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?

Front-loaded with the one-line purpose, then clean Args/Returns blocks with zero filler. Every sentence earns its place, including the cost note and the routing caveat.

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 one-parameter polling tool with no output schema, the description supplies the return field set (ok, kind, job_id, status, percent, step, video_url, error), which is exactly what's missing structurally. Minor gap: no guidance on whether status is terminal or how often to poll.

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 0% and the schema only constrains job_id to a string under 100 chars, so the description carries the load: it enumerates the accepted id prefixes (r_/a_/au_ for render/analysis, v_ for AI clip, m_ for music, t_ for voiceover), which meaningfully disambiguates the parameter.

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 ('The status of a long-running job') and scopes it to concrete job types (render, AI clip, music track, voiceover). It also distinguishes itself from the project-result path by telling the agent that studio-internal jobs report here but their result is read via studio_get_project.

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?

Clear context for when to call: polling a long-running job, with explicit routing for studio-internal results to studio_get_project. It does not explicitly contrast with siblings like wait_for_job or cancel_job, so the 'when not / alternative' half is left implicit.

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