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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context with 'Key values are never shown again', warning the agent that secrets are not retrievable through this call. It stops short of describing whether revoked keys appear or what metadata fields are returned.

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?

Two short sentences, zero waste. The scope statement comes first and the critical caveat about key values is front-loaded as the second sentence.

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-only list tool with no output schema, this covers the essentials plus the important secret-visibility caveat. The only gap is that it never hints at what the returned records contain (key IDs, names, creation dates) or whether revoked keys are included, which the agent needs to chain into apikey_revoke.

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 tool takes zero parameters, so there is nothing for the description to clarify; baseline 4 applies. Schema coverage is 100% and empty, consistent with the description.

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 (Lists) and resource (API keys) and scopes it to 'this agent's', which distinguishes it from org-wide key or registration-token listings. It does not explicitly name the sibling alternatives (apikey_create, apikey_revoke, regtoken_list), but the verb/resource pair makes the read-only enumeration purpose unmistakable.

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?

Usage is implied by the name and description: enumerate existing keys to find IDs for later revoke operations. There is no explicit statement of when to use this versus regtoken_list or org-level key tools, and no prerequisites or exclusions are given.

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