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

Annotations declare readOnlyHint=false and idempotentHint=true, and the description reinforces idempotency implicitly while adding genuinely valuable context beyond the annotations: 'This tool moves no money' disambiguates a payment-named tool, and the stated auth paths clarify prerequisites. It does not cover failure modes or what happens on retry, keeping it short of a 5.

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 tight sentences with the core purpose front-loaded, followed by the money clarification and the auth conditions. Every sentence carries information and nothing is padded.

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 2-parameter, no-output-schema tool with supporting annotations, the description covers purpose, the no-money behavior, and the three valid auth states. It lacks only a clear sibling distinction against create_list_payment_link, which is the one meaningful gap.

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 coverage is 100%, so both parameters are fully documented in the schema itself, establishing the baseline of 3. The description's mention of the trial_code auth path adds a little framing but no syntax or format detail beyond 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?

States a specific verb (returns a page) and resource (buying WozApi credits for single lookups) paid via iDEAL. It is clearly distinguishable from lookup_woz_value and get_account_balance, though it never explicitly contrasts itself with the sibling create_list_payment_link, which is the closest 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?

It describes the auth conditions under which the tool works (signed in, API key, or trial_code), which is useful context. But it gives no explicit guidance on when to choose this versus create_list_payment_link (a credits purchase vs a list purchase), leaving the key routing decision to inference.

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