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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description still adds real value by disclosing the security constraint (OAuth security:read required) and clarifying that secrets are never returned, which is exactly the kind of context an agent needs for a credential-adjacent tool.

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 filler. The returned-field inventory and the security guarantee are front-loaded, and the auth prerequisite follows compactly.

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?

This is a zero-parameter read tool with an output schema, so return values need no explanation. Between the annotations (safe read), the stated scope requirement, and the 'never secrets' guarantee, an agent has everything needed to 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?

The tool takes zero parameters, so the baseline is 4. There are no parameters to misdescribe and the description correctly implies a no-argument listing operation.

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?

Specific verb (list) plus resource (account API keys) with the returned fields enumerated: IDs, labels, prefixes, dates. This clearly distinguishes it from create_account_api_key, revoke_account_api_key, and rotate_account_api_key in the sibling set.

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 'never secrets' clause and the OAuth scope imply the intended use (inspect existing key metadata), but there is no explicit when-to-use statement or reference to alternatives such as revoke/rotate/connected-apps listing. Usage is inferable rather than stated.

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