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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds meaningful behavior beyond annotations: owner-only authorization, zero cost, and the contribution state lifecycle including the consequence that pending contributions are not used in the video. It does not discuss pagination or rate limits, but those are less critical for a simple list operation.

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?

The description is a single dense sentence with a front-loaded purpose and useful parenthetical detail. Every clause contributes information about fields, states, access, or cost. The colon-heavy structure is slightly hard to parse but remains efficient.

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 read-only listing tool with no output schema, the description provides strong context: the source of the files, the returned fields, the state semantics, the owner-only restriction, and the cost. The main remaining gap is that it does not explicitly document the project_id parameter or the response envelope. These are minor compared with what is already covered.

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 0%, so the description must compensate. It contextualizes the required parameter indirectly by describing the target as a piece, which maps to project_id, but it never explicitly defines project_id or confirms that the piece is identified by that parameter. The sole parameter is simple and required, so the ambiguity is limited.

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 and resource: listing files third parties sent to a piece via guest upload links. It also enumerates returned fields and contribution states, so the agent understands what is being retrieved. It does not explicitly contrast itself with the sibling accept_contribution, which is the closest related operation.

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?

The description gives useful usage constraints: only the piece owner may call it and it costs $0. It also explains that pending contributions are not yet used in the video, implying the tool is for reviewing guest submissions. However, it does not explicitly say when to use this versus accept_contribution or other listing tools.

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