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

Beyond the readOnlyHint and destructiveHint annotations, the description explicitly discloses that only a masked preview is ever shown and that the tool never returns actual secret values. It also adds the authentication precondition and the scope of included credential types.

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 compact and front-loaded, with each sentence adding a distinct piece of information: scope, output fields, masking guarantee, credential types, and auth requirement. No filler or restatement of the title.

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 zero-parameter, read-only list tool, the description fully covers what the agent needs to know: what the tool lists, what fields are returned, that values are never exposed, and that authentication is required. There is no output schema, but the description supplies the essential return expectations.

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 has zero parameters and the schema is fully clear with no properties to describe. The description correctly avoids inventing parameter details, and the baseline for no-parameter tools applies.

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 resource 'your saved keys & secrets', with concrete detail on what each entry contains: provider, ALIAS via secret_refs, and a masked preview. This distinguishes it from other listing tools by scoping it specifically to stored credentials.

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 gives clear context: it is for listing masked saved keys, covers pasted API keys, custom secrets, and OAuth grants, and requires a logged-in identity. It makes the 'when-not' explicit by stating it NEVER returns a value, though it does not name an alternative tool.

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