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

Annotations already flag destructiveHint=true and idempotentHint=false, but the description goes well beyond them: it discloses partial-update semantics, that [] CLEARS a select/reference field, that previous values are not retained (no undo), and that Beacon workflows may fire as a side effect. These are exactly the consequences an agent needs before mutating data.

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?

Five short clauses, front-loaded with the 'WRITE:' marker and the operation summary, then the highest-risk behaviors. No filler sentences and every clause carries distinct information.

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 mutation with no output schema and annotations covering only the safety profile, the description covers clearing behavior and side effects well. It omits error behavior for a nonexistent id and any permission requirements, which would be the remaining gaps.

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 the baseline is 3, but the description adds real value beyond the schema: the empty-array-clears-a-field rule is not derivable from the schema, which only says select fields are arrays. It still does not restate field-key lookup guidance, which the schema already handles.

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 — 'change fields of ONE existing record' — and the 'ONE' plus 'existing' phrasing implicitly separates it from create_record, upsert_record, and delete_record siblings. The PATCH endpoint confirms the operation unambiguously.

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?

'ONE existing record' implies the record must already exist, which is the key discriminator against upsert_record. However, no sibling is named and there is no explicit statement of when to prefer this over upsert_record or create_record, leaving the routing inference to the agent.

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