Buy portable endpoint evidence

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

It discloses that this is a paid action spending sandbox credits, that issuance precedes charging, that failures do not bill, and that completed x402 purchases can recover results without additional charges. It also cautions that the signature proves origin/integrity, not observation truth or endpoint safety, which is valuable beyond the annotations.

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 organized into clear thematic blocks (payment flow, return contents, verification, caveats) and each sentence carries relevant behavioral or usage information. It is not overly verbose for the complexity of a paid, two-step evidence operation.

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?

It covers the payment workflow, expected return contents, available verification paths, and important caveats. Although the full output schema is not shown, the description's summary of the evidence v2 fields plus the verification guidance makes the tool's behavior sufficiently complete.

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 has no descriptions, but the prose maps all five parameters to behavior: URL, TTL, optional audience, x402_payment metadata, and api_key spending credits. It does not provide detailed formats or constraints, but it compensates for the 0% schema coverage enough to orient an 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 clearly identifies the tool as a paid operation to obtain a signed, portable endpoint observation, with the title reinforcing 'Buy portable endpoint evidence'. It distinguishes itself from free alternatives like guild_evidence_verify and guild_preflight.

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 explains the two-step flow: first call with URL, TTL, and optional audience for a quote, then retry with x402/payment metadata. It explicitly points to guild_preflight for live checks without a bundle and to guild_evidence_verify/SDK for verification, giving clear when-to-use guidance.

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