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

With no annotations, the description carries the full behavioral burden. It discloses per-call costs, the pay-per-call x402 requirement, the exact error behavior when the payment-signature header is absent, mode-specific behavior, and the PASS/FAIL/REVIEW return shape with reason codes and evidence packet.

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?

Every sentence earns its place. The description front-loads the purpose, then densely packs mode selection, pricing, return format, and payment behavior without wasted words.

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 complex paid tool with no output schema, it covers the input format, mode selection, costs, return values, and failure behavior. The only minor gap is the exact payment-signature header format and precise evidence-packet structure, but the description states that error data carries payment terms, giving the agent a recovery path.

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 already documents both params at 100% coverage, but the description adds crucial meaning by explaining that mode lives inside the JSON input and by defining static, simulated, and repair semantics plus their costs. It does not further explain the context parameter, but the schema already handles that optional field.

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 a specific verb-resource pair: 'Validate and repair an n8n workflow JSON before production.' This clearly distinguishes it from the marketing, content, and analysis siblings, and the mode breakdown further clarifies the exact scope of operation.

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 clear situational context ('before production') and defines three modes with distinct purposes: static for deterministic checks, simulated for dry runs, and repair for patch generation. It does not explicitly name alternative sibling tools or exclusions, but the n8n-specific scope makes the intended use unambiguous.

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