get_relationship

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds genuinely new behavioral detail beyond that: the return shape (relationship in words plus generation distance to common ancestor) and the failure mode (`related` is false when no common ancestor is found within search depth). It stops short of 5 since it says nothing about performance, limits, or behavior on unknown/invalid person identifiers.

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?

Three short sentences, front-loaded with the core action, then the return shape, then the failure-mode caveat. Each sentence carries information; only the parenthetical aside is slightly decorative.

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?

With no output schema, the description correctly fills the gap by explaining what is returned (words + generation distance) and the `related` flag semantics. All four parameters are schema-documented. Minor gaps remain around error behavior for bad handles and the server default depth.

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 the baseline is 3. The description adds only marginal meaning — the notion of a depth-limited search and that the default reports the closest relationship (implying all_paths=false) — but contributes no syntax or format detail beyond the schema.

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 gives a specific verb+resource ('work out how two people in the tree are related') that is inherently distinct from directional siblings like get_ancestors and get_descendants. It does not explicitly name those siblings, so an agent must infer the distinction, keeping it short of a 5.

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?

Usage is implied by the purpose ('how two people are related'), and it signals that a false `related` result is meaningful 'if you expected one,' which is interpretive guidance. However, there is no explicit when-to-use/when-not or named alternative versus get_ancestors/get_descendants.

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