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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description isn't carrying the safety burden. It still adds real value beyond them: it discloses that only metadata is returned and never secrets, and it states the required scope api_keys:read, which annotations do not cover. Minor gap: no mention of ordering or result size for large key sets.

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 sentences, front-loaded with the core action and the most consequential caveat (never secrets) before the usage routing. Nothing repeats the name or the schema.

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 no-parameter read tool with rich annotations, the description covers purpose, the security caveat, the required scope, and the downstream sibling. An agent has everything needed to select and call it 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?

Zero parameters, so there is nothing for the description to disambiguate and the 100% schema coverage baseline applies. The description adds no parameter detail and needs none.

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 (list this account's model API keys) and immediately scopes it as metadata-only, never secrets. That scope clause distinguishes it from any secret-returning operation and from the credit-balance sibling.

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?

Gives both a trigger (user asks which keys exist) and a chaining use (before revoke_api_key to find a key_id), plus an explicit exclusion pointing to get_api_credit_balance for balance questions. Lacks an explicit 'do not use create_api_key for this' statement but the routing is already clear.

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