updateRecord

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

Annotations declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, and the description is consistent with that by explaining the merge/preserve behavior that justifies non-destructiveness. It adds genuinely useful context beyond the annotations (what survives the call), but says nothing about the transactionId atomic-update semantics, permission requirements, or failure behavior, so it falls 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?

Two sentences, both front-loaded: the core semantics first, then the alternative and prerequisite. Every clause carries information an agent needs; nothing is redundant with the name, title, or schema.

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 mutation tool with an output schema already present, the description covers the essentials: what it mutates, what is preserved, the sibling alternative, and the prerequisite for the required recordId. Return values need not be described since the output schema exists, so nothing an agent needs to call this correctly 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 coverage is 100%, so the baseline is 3, but the description adds real meaning to the `data` parameter by defining it as a partial patch where absent fields are preserved — a semantic the schema's 'updated (partial) record data' only gestures at. It also motivates `recordId` by describing how to obtain it. It does not clarify `label` or `transactionId`, keeping it below 5.

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 precise verb+resource ('Partially update a record') and immediately qualifies the semantics with 'only fields present in data are changed; all other existing fields are preserved.' It explicitly distinguishes itself from the sibling setRecord, so an agent can route 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?

Names the alternative tool and the exact condition that selects it ('Use setRecord instead if you want to replace all fields'), and supplies a prerequisite workflow ('Requires recordId: retrieve it first with findRecords or getRecord if not already known'). Both when-to-use and how-to-prepare are covered explicitly.

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