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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does not state whether the tool is read-only or calls an external AI service, whether rate limits or API keys apply, what kind of response format to expect, or whether the input error is processed locally or sent externally. The phrase 'with AI' hints at an external service but gives no safety or latency context.

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 only one sentence and immediately leads with the tool's purpose. It is not verbose or padded. It earns a 4 because there is no wasted text, though a second sentence clarifying inputs or alternatives would have made it more useful.

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 AI-explain tool with two string parameters and no output schema, the description could still cover which input to provide, what kind of explanation to expect, and whether the call is side-effect free. Given no annotations and a sibling list full of ambiguous AI and explain tools, the description leaves the agent without enough context to invoke it correctly or confidently.

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 100%, but the schema descriptions are tautological: 'Error to process' and 'Message to process' add no meaning beyond the property names. The tool description also does not clarify the relationship between 'error' and 'message' — i.e., whether one is required, both should be supplied, or one can substitute for the other. With zero required parameters, the agent gets no guidance on how to populate this tool correctly.

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 states a specific verb ('Explain') and resource ('error message with AI'), so the core purpose is recognizable. However, it is nearly a restatement of the tool name, and it does not clarify what kind of explanation is produced (root cause, debugging steps, human-friendly summary?). It is also ambiguous against siblings like x402-ai-code-explain, x402-regex-explain, x402-sql-explain, and x402-tx-explain, which all 'explain' different things.

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?

No when-to-use guidance is provided beyond the implied 'provide an error message.' There is no mention of alternatives, exclusions, or cases where another tool such as x402-ai-code-explain, x402-code-diagnose, or x402-tx-explain would be more appropriate. The agent must infer usage from the name alone.

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