assets_sign

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

With no annotations, the description carries full burden. It discloses time-boxed nature, TTL defaults, and security benefit (no API key exposure). Missing details like whether the blob must exist or if the operation is idempotent, but provides key behavioral traits.

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, front-loaded sentences with no redundancy. Every sentence adds necessary information: action, use case, and constraints.

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?

While clear for a simple tool, it lacks description of the return value (presumed URL string) and does not mention prerequisites like blob existence. Given no output schema, the description should specify what the tool returns.

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 100%, so baseline is 3. The description reinforces the TTL parameter with default and max values, which adds value beyond the schema, but does not add new meaning for other parameters.

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?

The description clearly states the verb (generate) and resource (time-boxed S3 presigned GET URL for a blob). It differentiates from sibling tools like assets_get, assets_ls, etc. by specifying the purpose: sharing externally without exposing API key.

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?

It explicitly says 'Use this to share a private blob externally' and mentions the default TTL and max. While it doesn't list alternatives or when not to use, the context implies this is for external sharing vs direct API access.

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