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

Annotations already declare destructive=true, readOnly=false, idempotent=false, but the description adds genuinely new behavioral context: that this is a declaration rather than a verification ('No payment verification occurs') and that the agent must obtain explicit human confirmation first. It does not say what downstream effects the declaration triggers (e.g., releasing funds or notifying the counterparty).

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?

Three short sentences, front-loaded with the operation and its hard precondition, followed by the prohibition and the scope caveat. Every sentence carries distinct, load-bearing information with 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?

For a destructive, non-idempotent mutation with no output schema, the description covers the critical decision inputs: when it may be called and what verification does not happen. It omits post-call behavior (what state changes or notifications result), which would fully close the loop.

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 67% and all three parameters carry inline descriptions (including the actorId hint to use list_my_actors), so the schema does most of the work. The description adds no parameter-level meaning, 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?

States a specific verb and resource: recording a buyer's payment declaration. The phrase 'buyer declaration' implicitly contrasts with the sibling mark_payment_received, but the description never names or explicitly distinguishes that counterpart, so the boundary is inferable rather than stated.

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 a firm precondition ('ONLY after the user explicitly confirms the actual external payment') and an explicit prohibition ('Never infer payment from clicking a link'), which is stronger than most tools offer. It stops short of naming the alternative tool to use when payment has not been confirmed, so routing is not fully closed.

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