Vangrid observation

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

With no annotations, the description carries the full burden and does disclose the non-obvious behavior: this is a paid read, priced at roughly $0.005 USDC, payable on Base (eip155:8453) or Arc (eip155:5042). It also names the data returned and where attestation lives. It omits failure modes (unknown hash, unpaid call) but covers the critical commercial/payment traits.

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?

Two sentences, tightly packed, front-loaded with what is fetched and keyed on before moving to payment details. No filler.

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?

With no output schema and no annotations, the description compensates by enumerating the returned fields (coarse location, capture time, EAS attestation) and the payment rails. For a one-parameter read tool this is close to complete; only error/edge-case behavior is left unspecified.

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% with the single id parameter documented, so the baseline is 3; the description adds real value by clarifying the hash may be supplied with or without a 0x prefix, a format detail the schema does not state.

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 (fetch), resource (one anchored capture), identifier (sha256) and the returned content (location, capture time, EAS attestation on Base). However, it does not distinguish itself from the sibling vangrid_verify_provenance, which plausibly also operates on a capture hash, so an agent still has to infer the boundary between the two.

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?

Usage is implied by the purpose and the cost note ('paid per call... about $0.005') implicitly warns the agent to use it deliberately, but there is no explicit when-to-use vs. when-to-use-an-alternative guidance and no mention of verify_provenance or coverage_query as alternatives.

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