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

Annotations already supply readOnlyHint, idempotentHint, and destructiveHint, so the description does not contradict them. It adds value by noting the operation is free and that it returns a budget-guarded contract without performing payment, reinforcing the non-mutating behavior.

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 two sentences with no wasted words. It front-loads the most important facts ('Free/read-only'), then states the resource and the key negative behavior ('never performs payment itself').

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?

Given the output schema is present, annotations cover safety semantics, and the two parameters are fully described in the schema, the description is complete for this simple read-only tool. An agent has enough context to invoke it correctly without additional explanation.

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%, and both task_id and max_payment_usd already have meaningful schema documentation. The description's 'budget-guarded' phrasing aligns with max_payment_usd, but it does not add new parameter-level detail beyond what the schema provides, so the baseline of 3 is appropriate.

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 states a specific verb and resource: 'Returns a budget-guarded MPP contract,' and clarifies it is read-only. It also distinguishes itself from payment-executing siblings like fund_field_agent_task by noting it 'never performs payment itself,' though it does not name the alternatives explicitly.

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 clearly signals when to use it: when a read-only contract is needed but no payment should be executed. Phrases like 'Free/read-only' and 'It never performs payment itself' provide useful context, but there is no explicit statement of when to prefer a sibling tool for actual funding.

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