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

Annotations already declare the write, non-idempotent, destructive, open-world profile, but the description adds real value beyond them: the note is staff-private by default, is_public exposes it on the customer portal, and the return value is the new note id. The 'notes cannot be removed with this server' line usefully tells the agent there is no cleanup path. Slight tension with destructiveHint=true is worth noting, but it reads as metadata caution rather than a contradiction.

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 'WRITE:' mode marker front-loaded, followed by visibility behavior, return value, irreversibility, and the endpoint. Nothing is padded or repeated.

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 three-parameter write tool with no output schema, the description covers the mutation type, visibility semantics, the return shape ('new note id'), and the lack of a delete path. An agent has everything needed to call it correctly and interpret the result.

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 all three parameters (text, order_id, is_public) are fully documented in the schema. The description's statement about is_public largely restates the schema's 'Visible to the customer on the customer portal' text, adding no format, length, or ordering details beyond structured data.

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 and resource ('WRITE: add a note to an existing order') plus the underlying endpoint. The 'order' qualifier separates it from brightpearl_add_contact_note and the 'add' verb separates it from brightpearl_get_order_notes without opening any 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?

Usage is implied rather than stated: it clarifies the privacy default and notes that removals are impossible here, which nudges the agent away from expecting a delete path. However, no explicit when-to-use/when-not-to-use guidance or named alternatives are given (e.g. reading notes via brightpearl_get_order_notes, or contacting notes via brightpearl_add_contact_note).

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