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

The annotations already declare readOnlyHint=true and destructiveHint=false, so the agent knows this is a safe read operation. The description adds the singular 'by id' semantic but does not provide additional behavioral context such as missing-record behavior, authorization needs, or rate limits. This is acceptable because the annotations carry the safety profile.

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?

A single sentence with no filler, and the core operation is front-loaded. It is appropriately concise, though it adds little beyond the tool name and could include a small note about return behavior without sacrificing brevity.

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 single-record getter with a relatively simple input contract, the description is basically sufficient. There is no output schema, and the description does not indicate whether the tool returns a single object, returns null on missing ids, or throws an error. This is not critical for an agent to try calling it, but it leaves some return-behavior ambiguity.

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 input schema already documents id, companyName, and connectionRef, including the important session-rotation guidance for connectionRef. The description does not add parameter-level detail, but the schema handles that responsibility well. This matches the baseline where structured descriptions do the heavy lifting.

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 clearly states the verb and resource: 'Gets one BRC sales credit note by id.' It is distinguishable from list and batch siblings because it scopes the call to a single credit note and requires an id. It is specific and unambiguous, though it does not explicitly name related siblings.

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 implies usage: when you have a credit note id and need one record. It does not mention when to prefer brc_list_sales_credit_notes or brc_batch_sales_credit_notes. There is no explicit when-to-use or exclusions, so usage guidance is adequate but not strong.

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