Complete hold (capture funds)

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

With no annotations, the description carries the full burden. It discloses a key behavioral trait: 'NovaPay returns no body for this call,' and explains the state transition (holded to paid) and partial capture option. It does not cover failure modes or authorization requirements, but the disclosed behaviors are important and non-obvious.

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, front-loaded with the primary action, and no filler. The first sentence defines the core purpose; the second adds the crucial note about no response body and how to verify. Every phrase earns its place.

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 state-changing payment tool with no output schema, the description covers the essential aspects: what it does, a prerequisite, an option, and a verification step via get_session_status. It stops short of covering error handling or side effects beyond the state transition, but it is reasonably complete for an agent to operate correctly.

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%, with both parameters clearly described. The description adds a slight clarification of the amount parameter ('Optionally capture a smaller amount than was held') but mostly repeats schema information. The baseline of 3 is appropriate because the schema already does the heavy lifting.

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 clearly states the tool's action: 'Capture funds previously held with use_hold=true, moving the session from holded to paid.' It uses a specific verb (capture), resource (funds held), and context (use_hold=true), which distinguishes it from sibling tools like void_session and expire_session.

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 implies when to use the tool: after a hold created with use_hold=true. It also mentions the optional partial capture. However, it does not explicitly contrast with alternatives (e.g., void_session) or state exclusions, but the prerequisite and follow-up guidance ('check with get_session_status') provide clear usage context.

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