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

Annotations only flag destructiveHint=true and readOnlyHint=false; the description carries the real behavioral burden and does so thoroughly. It discloses that nothing is written until explicit confirmation, that routeToken does not bypass preview or confirmation, that a call without confirmWrite returns confirmation_required with a payload preview, and that confirmWrite applies the previewed change. This far exceeds what the annotations provide and aligns with the destructive/write nature of the tool.

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 dense — roughly nine sentences — but every sentence earns its place for a destructive transactional tool. The key safety fact ('Nothing is written until you confirm') is front-loaded early, and the structure flows logically from purpose to preview behavior to token requirements to confirmation protocol without repetition.

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 complex destructive tool with no output schema, the description is unusually complete. It explains the return behavior (confirmation_required plus payload preview), the token dependency on brc_route_request, and the exact confirmation sequence. Remaining parameters like connectionRef and companyName are fully covered by the schema, so nothing essential is missing.

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 every parameter (routeToken, confirmWrite, quoteId, procDate, entryDate, companyName, connectionRef) is already documented in the schema. The description reinforces the workflow semantics of routeToken and confirmWrite but does not add new per-parameter meaning beyond what the schema already states, so the baseline score 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?

The opening sentence 'Generates a sales invoice from a BRC quote' pairs a specific verb with a concrete resource and a distinct provenance. The 'from a quote' scoping clearly separates this tool from siblings like brc_create_sales_invoice (which creates invoices without a quote source), so an agent can tell them apart without opening either 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?

The description gives a concrete call flow: call without confirmWrite to receive a preview, show it to the user, then call with confirmWrite only after explicit confirmation. It also states exclusions — placeholder tokens are invalid and preflight is not confirmation. It does not explicitly name the alternative for quote-less invoicing, but the workflow guidance is specific enough to route correct usage.

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