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

Annotations include readOnlyHint: true, and the description aligns by saying it's a 'short-lived URL' for downloading, which is a read operation. It goes beyond annotations by disclosing the URL is short-lived, implying the agent should call it close to when the download is needed. It also clarifies the return type and that it returns bytes, providing useful behavioral context that the schema doesn't.

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 highly concise: two sentences. It packs crucial information in a short space, front-loading the purpose and then adding essential parameter context and return format. Every word adds value; no fluff.

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?

Given the tool's simplicity (one parameter, simple return), the description covers the essentials: what it does, how to get the id, and the return shape. It might benefit from noting the URL's expiration time, but the output schema existence reduces the need to detail the return structure. Overall, an agent has what it needs to call correctly.

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?

The schema has only one parameter 'id' with no description (0% coverage). The description compensates by explaining that 'id is the media memory's id (from create_upload / recall),' which directly adds semantics to the parameter that the schema lacks. Since there's only one param, this is sufficient.

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 tool's purpose: 'Get a short-lived URL to download a media memory's bytes.' It distinguishes itself from siblings like 'get_memory' and 'list_memories' by specifying it returns a download URL for media, not just metadata or full memory content. The verb 'Get' and the resource 'short-lived URL' are specific and informative.

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 implies the tool is for downloading media memory bytes, and it mentions the id comes from 'create_upload' or 'recall', giving context on when to use it. It doesn't explicitly say when not to use it or name alternatives, but the dependency on prior actions is clear, which is adequate for a simple tool with few siblings.

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