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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the bar is lower, yet the description still adds real signal: a 45-second wait bound, the enumerated whole-job states, and the explicit note that this is a free read that does not advance stages or charge credits. That no-charge/no-side-effect statement is exactly the kind of operational context annotations cannot carry. It is slightly redundant with readOnlyHint, which keeps it from a 5.

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 core behavior (wait, then return state) before the state enumerations and edge-case rules. Six sentences is on the long side and a few clauses are dense, but the enumeration and the picture-only/video/likeness rules are decision-relevant rather than filler, so little could be cut without losing meaning.

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 two-parameter read tool with full annotations and an output schema, the description is near-complete: it covers timing, idempotency-by-implication, the state vocabulary, and the guarantee of no side effects or charges. The remaining gap is the unstated relationship to the sibling studio_generation_wait, which an agent would need to choose between the two confidently.

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?

With only 50% schema description coverage, the description must carry weight, and it does: it tells the agent both parameters identify an existing saved operation and that operationId is the original id from a quote tool, and that picture-only approval covers only its quoted pictures. The schema documents operationId but leaves projectId bare, so the added provenance and scope meaning compensates meaningfully.

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?

Opens with a specific verb and resource: waits up to 45 seconds for an active rendering stage, then returns state and continuation data, and identifies the target as a saved whole-job or picture-only operation keyed by original projectId/operationId. That is far more than a restatement of the name. It does not, however, differentiate itself from the sibling studio_generation_wait, leaving the agent to infer which polling tool to pick.

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 clear context for use: call it for an already-approved operation, passing the operationId that originated from studio_generation_quote or studio_storyboard_stills_quote (the schema description names those sources). It stops short of explicit exclusions or a direct comparison against studio_generation_wait, so the routing decision is implied rather than stated.

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