get_facts

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

Beyond readOnlyHint/openWorldHint it discloses two behaviors the annotations cannot convey: living and private people are withheld by default and only shown when include_private is set, and the call is slow because the server computes results per call. It also frames implausible results as likely data errors, which shapes how the agent should interpret output.

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-loads purpose in the first sentence, then clarifies scope, interpretation, privacy, and cost in order. Every sentence contributes, though the privacy sentence duplicates the include_private schema description and the length is near the upper bound for a list-style tool.

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?

There is no output schema, and the description does not describe the shape of the returned record-holders (names, values, ordering by rank), which is the main remaining gap. Parameters, safety, privacy defaults and performance are all covered, so an agent has enough to decide and call, just not to anticipate the response.

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 100%, so all four parameters are already documented in the schema; the description's mention of include_private largely restates that. It adds only a light framing of the scope ('across a set of people'), which the schema's person_filter description already covers in more detail. Baseline 3 applies.

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 ('Read') and an unusual resource ('the tree's record-holders'), then immediately concretizes it with three examples: oldest at death, youngest parent, most children. The line 'Superlatives across a set of people, not statistics about one person' separates it from per-person getters like get_person or db_stats without requiring the schema to be opened.

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 a clear usage scenario ('a quick plausibility check' for data errors) and a condition on the include_private flag. However it never names an alternative tool or states an explicit when-not-to-use case, so the agent must infer routing from the purpose line alone.

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