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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful context beyond that: the operation performs a live connection sequence (initialize, tools, resources, prompts, auth check) and costs $0.004 USDC per call via x402 — a real behavioral/pricing constraint an agent should know before invoking.

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 action statement is front-loaded before the colon-list of internals, and every clause carries information (targets, handshake contents, vetting purpose, cost). It is dense but not padded; only the enumeration could be trimmed slightly.

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 one-parameter, read-only, open-world tool with no output schema, the description covers what is contacted, what is retrieved (skills, auth, llms.txt), and the per-call cost. It leaves the exact return shape unspecified, which is acceptable given there is no output schema, but the deliverable of an 'inspect' call could be framed more concretely.

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?

With a single parameter and 100% schema description coverage, the schema already documents that 'url' accepts an MCP endpoint or a site. The description's mention of 'remote MCP endpoint' adds no format or syntax detail beyond that, 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 (Inspect) and resource (another agent or MCP server), then enumerates exactly what gets inspected: MCP endpoint handshake, A2A agent card, and llms.txt. This clearly distinguishes it from siblings like http_inspect, openapi_inspect, and site_agent_ready.

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 phrase 'before using it' gives a clear trigger condition (vetting a counterparty prior to interaction), and 'Vet tools and partners automatically' reinforces the use case. However, it never names alternatives such as http_inspect or openapi_inspect for non-agent endpoints, nor states when not to use it.

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