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

Annotations already declare destructiveHint=true and non-idempotent, and the description reinforces this with 'Irreversibly declare.' Beyond the annotations it adds genuine behavioral context: evidence is excluded from trusted growth, it never promotes identity or targets another agent, and it explains credential handling (private argument or Authorization header, never in URLs or error output).

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 dense sentences that front-load the action and follow with scope, side effects, and credential handling. Every sentence carries information; phrasing is slightly loaded but not padded.

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 destructive, non-idempotent mutation with two parameters and no output schema, the description covers the critical decision inputs: irreversibility, identity scoping, exclusion from trusted growth, and credential transport. It is nearly complete, with only the traffic_class parameter semantics left thin.

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?

Schema coverage is 50%: the credential parameter is documented in the schema, while traffic_class carries only a single-value enum with no description. The description adds value by explaining the credential can alternatively be supplied via the Authorization header and is never echoed, but the traffic_class semantics beyond the enum value remain unstated.

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 names a specific action ('declare') and a specific resource ('only your own authenticated identity manual_probe'), and scopes it tightly to a single identity. It does not explicitly differentiate itself from the many sibling identity tools (register_agent, verify_agent, trust_record), so it lands at 4 rather than 5.

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 context is implied through 'for internal testing' and 'Excludes its evidence from trusted growth,' which signals this is a probe that deliberately does not feed the trusted pipeline. However, it never states when to prefer this over siblings like trust_record or register_agent, so guidance is only partial.

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