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

Beyond what annotations already provide, the description discloses authentication requirements (Bearer token or X-API-Key), guest-call restrictions, and the need for an already-opened session. It also adds the preference for open_tx_hash over proof_escrow_id. It does not detail side effects on funds or what happens on re-attach, but the annotations already convey idempotency and non-destructiveness.

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 compact and front-loaded with the core purpose, then moves to access requirements, the attachment action, and the REST endpoint. Every sentence carries actionable information, with no filler or restatement of the tool name.

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 tool involved in a paid workflow without an output schema, the description covers the essential invocation details: purpose, auth, prerequisites, parameter preference, and endpoint. It would be slightly more complete with an explicit pointer to the funding prerequisite and the follow-up query step, but an agent can still call the tool correctly from the information provided.

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 only 33%, so the description must compensate. It adds useful selection semantics by stating open_tx_hash is preferred or proof_escrow_id can be used, and clarifies session_id refers to an opened data session. However, it does not explain how to obtain open_tx_hash or what proof_escrow_id represents beyond the name, leaving some parameter meaning under-specified.

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 uses a specific verb and resource: attach a buyer-funded proof escrow to an opened data session. It also communicates the higher-level outcome (buy per-query access) and distinguishes itself from data_preview by calling that the free alternative. The REST endpoint removes any remaining ambiguity.

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 gives concrete usage context: requires an agent API key, is not guest-callable, requires an opened data session, and names data_preview as the free alternative. It clearly implies the escrow must already be funded, though it does not explicitly point to data_session_fund or data_session_funding_package as the prerequisite sibling tools.

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