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

The description adds meaningful behavioral context beyond annotations: it discloses the $0.006 USDC cost, states that missing fields become null, and promises 'never invented', which is a strong anti-hallucination guarantee. It does not elaborate on payment mechanics or rate limits, but the payment_signature parameter is documented in the schema.

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 two short sentences with no filler, front-loading the cost and then stating the core operation and guarantee. It is appropriately compact, though it sacrifices some explanatory richness for brevity.

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?

The description plus schema provides a minimally viable picture: what goes in, what comes out, and the key null-behavior guarantee. However, there is no output schema, no explanation of how to encode `fields`, and no routing guidance relative to sibling tools, so the agent still has to infer several important details.

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 only 33%, so the description must compensate for the undocumented `text` and `fields` parameters. It relates 'any text' to `text` and 'YOUR fields' to `fields`, but it never explains how to structure the `fields` object (e.g., field names mapped to extraction instructions), leaving a meaningful ambiguity for the agent.

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 action: 'Extract YOUR fields from any text as JSON'. It clearly identifies the resource (arbitrary text), the customization (YOUR fields), and the output format (JSON). This is distinct enough from siblings like genesis402_web_extract because it targets any text rather than a specific source type.

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 guidance about when to use this tool versus the many siblings, nor any mention of when not to use it. The phrase 'any text' implies broad applicability, but no alternatives or selection criteria are provided.

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