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

The description adds useful behavioral detail beyond the schema by explaining what limit does and clarifying inclusive behavior ('node + its parent'). With no annotations, the full burden falls on the description; it covers core behavior but omits output ordering, return format, or behavior for unknown haplogroups, so it is adequate but not rich.

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 core information is front-loaded and expressed in two sentences. The bilingual duplication adds length without new information, slightly reducing conciseness, but the structure remains tight and readable.

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 simple read tool with no output schema and no annotations, the description gives enough to make a basic call, but it does not fully describe the expected return shape or edge-case behavior. An agent would likely call correctly, but the missing return-format detail leaves some ambiguity.

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%, and the description still adds value by illustrating limit semantics with a concrete example. It clarifies that limit=2 means the starting node and its direct parent, which is more precise than the schema's 'most recent N levels'.

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 names the exact operation ('Get the lineage chain from a haplogroup up to ROOT') and clearly differentiates this from sibling tools like children_haplogroups or subtree_haplogroups by focusing on the upward path to ROOT. The verb-resource pair is specific and immediately actionable.

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?

It gives concrete guidance for the limit parameter ('limit=2 for the node + its parent'), which helps with invocation. However, it does not explicitly state when to choose this tool over siblings or when not to use it, so the selection guidance is mostly implied by the purpose rather than stated.

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