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

With no annotations, the description carries the full burden of behavioral disclosure. It explains the exact USDC payment amount and recipient, HTTP 402 for unpaid requests, JSON being returned only after a valid X-PAYMENT, empty since results yielding 304 or recordCount 0, and the 'not a new SKU' distinction. This is unusually transparent for a paid endpoint.

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 dense but efficient: endpoint, payment, and call variants are front-loaded, and every clause adds a distinct fact. The run-on punctuation and the cryptic 'Not a new SKU' cost some readability, but there is no fluff or repetition.

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 five-parameter tool with no annotations and no output schema, it covers payment flow, pagination, watermarking, and error statuses well. The main gap is that it does not describe the structure of the returned JSON after payment, which an agent would need to reliably extract the enforcement-notice text.

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%, so the baseline is 3. The description adds pricing per parameter mode, defines before as 'next older chunk', since as a watermark, and clarifies that x_payment is forwarded as the X-PAYMENT header. This is meaningful value beyond the schema, though the schema already documents the basic page/since/before behavior.

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 identifies the resource as ORR Railways Act s.55 enforcement-notice text and maps each query mode to a distinct content type: one official text via ?id=, newest chunk via plain GET, older chunk via ?before, and newer-than-watermark via ?since. This is more than a name restatement, though it never states a clean verb like 'retrieve' and relies partly on the tool name for domain context.

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 call-selection context: plain GET returns the newest chunk, ?before fetches an older chunk, ?since returns items newer than a watermark, and ?id= fetches one official text. It does not explicitly route away from sibling tools or name alternatives, which prevents a 5, but the mode-by-mode guidance is strong.

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