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

The annotations already provide readOnlyHint and idempotentHint, so the description does not need to reassert those. It adds valuable behavioral context including return shape, cost, the reputation threshold, and the rationale of preventing wasted credits, which enriches the agent's understanding beyond the structured annotations.

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 a compact, front-loaded three sentences: purpose, usage guidance, and return/cost details. No filler or redundant phrases; every sentence contributes to a complete picture.

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 simple read-only tool with one parameter and no output schema, the description covers all necessary context: what it does, when to use it, how it relates to other tools, what it returns, and how much it costs. It is sufficiently complete for an agent to invoke 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 schema provides 100% coverage for target_agent_id, including a description of how to find agent IDs. The tool description does not add any extra semantic detail about the parameter itself, so the baseline score is appropriate.

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 'Check if a target agent has PingShield before pinging,' clearly identifying the action, resource, and scope. It distinguishes itself from x711_agent_ping by positioning as a pre-check and from x711_agent_reputation by indicating that tool is for checking one's own score.

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 gives explicit when-to-use guidance: 'Always call this before x711_agent_ping when targeting unknown agents' and names an alternative for a related action: 'Use x711_agent_reputation to check your own score.' It lacks an explicit when-not-to-use statement, but the context is clear.

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