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

With no annotations, the description carries the burden, and it does disclose two real behavioral traits: output composition (added/removed line blocks plus hashes) and that the call costs $0.001 USDC on Base via x402. It omits the maxLength 125000 input ceiling and any detail on how the x402 payment is authorized.

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?

Two tight sentences, front-loaded with the operation and return shape before the cost. Nothing redundant, though the pricing clause is slightly crammed into the same breath as the output description.

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 paid, undocumented-schema tool with no output schema and no annotations, the description covers purpose, return shape, and cost, but leaves input limits and the payment/auth flow unexplained. Adequate but not complete for an agent that must spend funds to call it.

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 description coverage is 0% across two parameters, so the description must compensate. It indicates two text values are compared but never maps before vs after semantics and ignores the 125,000 character limit, leaving meaningful gaps.

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 verb (compare) and resource (two text values) and states the return shape (added/removed line blocks, deterministic hashes), which cleanly separates it from siblings like text-stats or text-chunk. It does not explicitly name a sibling alternative, so it stays 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?

There is no statement of when to use this tool versus alternatives, nor any prerequisite or exclusion guidance. The only usage-relevant signal is the cost note, which tells the agent this call spends money but not when it is the right call.

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