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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description only needs to add context. It adds valuable detail about permission filtering ('the user can access') and the return content (metadata needed for graphId parameters), which is useful beyond the annotations.

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 two sentences: the first states the purpose and return contents, the second provides usage guidance and its relationship to other tools. Every word adds value, with the key information front-loaded. No redundancy or filler.

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 simple list tool with one optional parameter, no output schema, and safe annotations, the description sufficiently covers what the tool does, what it returns, and how to use it in a session. It fully compensates for the absence of an output schema by enumerating the fields returned.

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 input schema covers the single optional parameter (userId) with a complete description, achieving 100% schema coverage. The tool description itself does not add additional meaning to the parameter beyond what the schema provides, so a baseline score of 3 is appropriate.

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 'List' and the specific resource 'expert knowledge graphs the user can access', enumerating exact fields returned (IDs, descriptions, authors, sectors, signal counts, topic coverage). This differentiates it from sibling tools like search_graph or get_node, which serve different purposes.

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 explicitly instructs to 'Use FIRST in any session to discover available sources before searching', providing clear when-to-use context. It also explains that the tool returns graphId parameters needed by other tools, but does not mention explicit when-not-to-use scenarios or alternatives beyond the general search context.

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