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

With no annotations, the description carries full burden. It discloses that the tool returns stored data and does not perform live scans, which adds transparency. However, it fails to explain the meaning of the 'id' parameter or the concept of an 'indexed endpoint,' leaving gaps in understanding the tool's behavior.

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 concise at two sentences, with the purpose stated upfront in the first sentence. It avoids fluff and is well-structured, though it could be slightly more informative without sacrificing brevity.

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, no output schema, no annotations), the description is incomplete. It does not explain what the 'id' parameter represents, what a 'check' is, or the return format. This leaves the agent with insufficient information to invoke the tool 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?

The schema has one parameter 'id' with 0% description coverage, and the tool description does not mention or define this parameter. It provides no additional meaning beyond what the schema already shows, failing to compensate for the lack of schema documentation.

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 it returns the most recently stored check for an indexed endpoint, using a specific verb and resource. It distinguishes itself from siblings like get_mcp_endpoint by focusing on a stored check rather than the endpoint itself, and clarifies it does not scan URLs.

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 provides no explicit guidance on when to use this tool versus alternatives. It mentions it never scans an arbitrary URL, implying a limitation, but does not name sibling tools like get_mcp_endpoint or explain scenarios for choosing one over the other.

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