get_caller_identity

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

With no annotations provided, the description carries the full burden and reveals a key behavioral constraint: ERC-8128 signed requests are required, and it notes the effect on resolution (wallet to ENS name, metadata, portfolio). It also references setup documentation, adding useful context beyond the bare functionality.

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 efficient and front-loaded: the first sentence states the core purpose, subsequent sentences add essential context (auth requirement, setup pointer) without fluff. Every sentence contributes value, and it is appropriately sized for a zero-parameter read tool.

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 tool with no parameters and no output schema, the description is remarkably complete: it explains what the tool returns, the authentication prerequisite, and when to call it. It also links to setup details, leaving no obvious gap for the agent to invoke or interpret results.

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 input schema is empty with zero parameters, so there is nothing to explain. The description avoids inventing parameter details, and the baseline for a no-parameter tool is 4; it doesn't need to add parameter semantics.

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 opens with a specific verb+resource: 'Returns the authenticated identity of the calling agent,' and then details what that includes (ENS name, agent metadata, portfolio summary). This clearly distinguishes the tool from the many ENS-related siblings, as it is uniquely focused on the caller's own identity.

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?

It explicitly instructs to 'Call this first to confirm your identity is recognized,' providing clear situational guidance. It also points out the authentication prerequisite, though it doesn't contrast with alternatives or state when not to use it, but no direct substitute exists among the siblings.

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