entity_create

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

Annotations only say readOnlyHint=false and destructiveHint=false, which the description is consistent with. The description adds substantial behavioral context beyond that: the verbatim rule for text/accountText, the at-most-one owner constraint, statement length bounds, absolute-date requirement, inference/basis marking, and the return shape. It does not cover error/idempotency behavior, keeping it just short of the top band.

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?

Front-loaded with purpose, then constraints, with no filler sentences. The dense semicolon-chained phrasing is information-rich but slightly harder to scan than a cleanly separated list of rules.

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 9-parameter, nested-object tool with no output schema, the description supplies the return shape ({entityId, version, accountId, added}) and covers the highest-risk fields (text, accountText, owner, statements). Parameters like via, aliases and accountSource are left to the 89% schema coverage, which is acceptable but leaves minor 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 already 89%, so the baseline is 3, but the description adds real meaning: it clarifies the verbatim rule (trimmed, never summarized, only the part about this Entity), tightens owner to 'at most one', and explains that statements are the agent's one-fact interpretation with basis for inferences. This goes beyond the schema text rather than repeating it.

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 (Create) and resource (an Entity), then defines the resource precisely as 'one specific person, animal, thing or place that recurs across Events or applications.' It also distinguishes the tool from the alternative modeling choice (a criteria ref on the Event), so an agent can tell what this tool is for without opening the 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?

Explicitly routes the agent: 'Search first (entity_search)' names the sibling to check before creating, and 'otherwise use a {criteria} ref on the Event' states the condition under which this tool is NOT the right choice. Both when-to-use and the alternative path are present.

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