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

Annotations already declare destructiveHint=true and idempotentHint=false, but the description adds real context: what actually changes (the invoice's paid status), that the change 'is not reversible from the API', and that a confirm:true gate plus explicit user approval of the amount is required. It does not cover failure behavior or permission requirements, so it stops 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 short sentences, front-loaded with the action and its effect, followed by prerequisites and the endpoint. Nothing is padding and no sentence merely restates the tool name.

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 a nested collect object and no output schema, the description covers effect, irreversibility, and the confirmation requirement. It leaves some gaps (permission/auth needs, what a failed or partial collection returns), but nothing that would cause an agent to invoke it incorrectly.

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 80%, so the baseline is 3. The description reiterates the confirm:true gate and parenthetically lists payment channels (receipt, bank order, card) that map to the collect.type enum, but it adds no syntax, defaults, or constraints beyond what the schema already documents.

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?

It names a specific verb and resource ('Record that an issued invoice was paid') and even pins the endpoint (PUT /api/docs/invoice/collect). That is clearly distinct from sibling actions like oblio_issue_invoice, oblio_cancel_document, and oblio_restore_document, so an agent can select it without opening the schema.

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 states hard preconditions for use: 'Needs confirm: true and the user's approval of the amount' and 'Not retried'. That is clear context for when to call it, but it never names an alternative or a when-not condition (e.g., partial vs. full collection, or how it differs from cancel/restore), so routing is implied rather than explicit.

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