fact

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

With destructiveHint=true already flagging danger, the description adds important behavioral detail beyond annotations: 'edit (all fields replaced)', delete is an available action, and date strings outside the approved formats are 'stored unparsed and never matches records or hints.' This meaningfully discloses side effects and data-matching consequences.

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?

The description is dense but every sentence carries essential information: resource scope, actions, dependencies, date grammar, and place ordering. It is front-loaded with the core purpose and then expands into constraints. It could be better organized with clearer separation between actions, but it avoids wasted words.

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?

The description covers many operational details and constraints, especially date parsing and citation/media workflows. However, it does not specify required parameters per action (e.g., what an 'add' minimally needs beyond action), and with no output schema it also does not describe return behavior. These are meaningful gaps for a complex 15-parameter tool.

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 only 33%, but the description substantially compensates by explaining action-specific parameter roles: spouseId for relationship events, assertionId for edits, citationId with databaseId/recordId for record citations, mediaId for media attachments, and detailed date/place formatting. Some parameters remain unexplained or implicit, such as treeId, showOnLifeStory, and description, so it is not a perfect compensation.

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 identifies the resource as 'Facts/events on a person' and enumerates the supported action verbs (list_types, add, edit, delete, attach/detach citation/media). This makes the tool's domain and scope obvious and distinguishes it from sibling tools like person, source, and record.

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 provides rich operational guidance, such as edit requiring an assertionId from person.get, relationship events requiring spouseId, and citation attach needing databaseId+recordId for record citations. However, it never explicitly states when to choose fact over alternative sibling tools or when not to use it, so the usage context is implied rather than explicit.

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