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

Goes well beyond the annotations by disclosing pricing tiers, the exact webhook payload semantics (HMAC-SHA256 signed JSON on fingerprint/grade change or reachability transitions), payment methods (x402 or credits key), that the signing secret is shown once, and that this call returns payment instructions rather than creating the watch directly. This is exactly the kind of operational detail an agent needs for a paid, non-idempotent mutation.

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 most important fact—that this is a paid validation call that returns payment instructions—is front-loaded in the first sentence. The remaining details are dense but each earns its place; the one weakness is that the payment-flow sentence is somewhat run-on and could be split for easier parsing.

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 tool with no output schema, the description covers cost, payment endpoints, webhook behavior, and the response contents (watch_id and signing secret). It does not fully clarify whether watch_id and the secret come from the MCP call or from the subsequent POST /v1/watch, leaving a small ambiguity about the exact end-to-end flow.

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 100%, so all three parameters are already fully documented in the schema, including defaults, enum values, and per-interval pricing. The description adds little parameter-level meaning beyond what the schema provides, so the baseline of 3 applies.

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?

States a specific verb and resource: it re-audits a public remote MCP server on a 24h/6h schedule and sends signed webhook notifications on changes. It also clarifies that the MCP call itself only validates and returns payment instructions, which is a crucial distinction. It doesn't explicitly contrast with siblings like check_mcp_server or audit_tools, but the 'watch' framing makes the ongoing-monitoring purpose clear.

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?

The description establishes context (paid only, validates and returns how to pay, requires an https webhook) but never states when to choose this over one-off checks like check_mcp_server or audit_tools, nor does it mention watch_status/watch_cancel. Usage is implied by the monitoring scenario rather than explicitly guided.

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