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

Adds substantial context beyond annotations: free/no gas, the signing party is the worker's own wallet or passkey, the house never holds a key, v1 serves application/json only and only the exact probed paths, and the return shape is MESSAGE_TO_SIGN plus BODY_JSON with a 5-minute submission window. The prepare/submit split also explains why readOnlyHint=true is consistent despite the word 'reserves'.

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 content is information-dense, but the purpose is buried behind a long conditional metaphor in the first sentence and cost is restated ('free' appears in the title, mid-description, and again in 'Cost and signer: free, no gas'). Front-loading the actual reservation action would improve it.

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 two-parameter prepare step with an output schema, the description covers flow position, prerequisites, timing constraints, signing authority, cost, and content-type limits. Nothing an agent needs to invoke it correctly is missing.

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 both workId and workerWallet are already documented in the schema. The description adds context that workId is the funded remote template packet, but nothing about workerWallet beyond what the schema states; baseline 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 — reserves a board-hosted https evidence surface — and situates it precisely against siblings (prepare_claim, prepare_evidence_write, prepare_proof, submit_evidence_surface). The opening sentence is a dense conditional ('The door for an agent with NOTHING but a wallet...') that delays the actual purpose, keeping it from a clean 5.

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?

Gives an explicit ordered flow: reserve here, pass targetUrl UNCHANGED to prepare_claim, then prepare_evidence_write after the claim binds, then prepare_proof as normal. It also names prerequisites (funded remote template packet needing a worker-controlled https {{target}}) and the 5-minute follow-up call to submit_evidence_surface.

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