Update a record

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

Annotations only declare readOnly=false, idempotent=true, destructive=false; the description goes well beyond that by disclosing merge semantics ('fields you leave out keep their values'), the null-to-clear convention, key validation that rejects unknown keys and returns the valid set, and that `relationships` only adds links and never removes them. It also states the return payload shape. This is exactly the mutation-specific behavior an agent needs before writing.

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?

Four tight, front-loaded sentences that each carry operational information, starting with the core verb+scope before the field-level rules. Minor redundancy with the `fields` schema description for the relationships behavior keeps it from a 5.

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 two-parameter mutation with nested `fields` and an output schema, the description covers everything an agent needs: id sourcing, merge vs clear semantics, validation failure mode, link accumulation, and return contents. Nothing material is left to inference.

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 a 3 is the baseline, but the description adds meaning the schema does not: omitted keys are preserved and explicit nulls clear a field. The `relationships` and unknown-key semantics are largely restated from the `fields` schema description, so the gain is real but modest.

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 plus its precise scope: 'Updates some fields of one record by id', which immediately signals a partial (merge) update rather than a full replace. It also names heliyos_records_list and heliyos_records_lookup as the id sources, so an agent can distinguish it from the read siblings without opening a 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?

Gives clear operative context: get the id from heliyos_records_list or heliyos_records_lookup before calling, and omit fields you don't want changed. It stops short of explicit exclusions — it never contrasts itself with heliyos_fields_update (schema/field definitions) or states what to do when the record doesn't exist.

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