update_payment

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

Annotations provide idempotentHint=true and non-destructive flags, but the description adds no behavioral details beyond the schema. It does not explain side effects such as invoice status updates, authorization requirements, or whether partial payments are allowed.

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 a single, concise phrase, but it lacks structure (e.g., separate notes or usage). While short, it is too terse to be adequately informative for an AI agent.

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 payment tool with 4 required parameters and no output schema, the description is incomplete. It fails to explain the tool's action (update vs. record), how it interacts with the invoice, or what the response contains. The contextual completeness is insufficient given the tool's complexity.

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 the description adds no additional meaning. It does not clarify relationship between price and invoice amount, or explain payment method enum values. The tool description is redundant with the schema.

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 translates to 'Record payment to an invoice,' but the tool name is 'update_payment,' creating a mismatch between action and name. It does not clearly state whether it creates or updates a payment, nor does it differentiate from sibling tools like delete_payment or get_payment.

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?

No guidance on when to use this tool versus alternatives. The description lacks context about prerequisites (e.g., does the invoice need to exist?) or exclusions (e.g., when to use other payment tools).

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