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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so safety is covered. The description adds genuine behavioral context beyond that: the edge source is Form-4 filings and the edge meaning is shared named persons, which tells the agent how to interpret results and the limits of coverage (officer-level overlap only).

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?

A single front-loaded sentence that defines the resource first and the edge semantics second, with no filler. It is dense and slightly overloaded with three slash-separated edge labels, but every clause carries information.

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 must convey what comes back, and it does state that results are other companies linked by shared Form-4 named persons. It stops short of describing result shape, ranking, or limits, but for a one-parameter read tool with full annotation coverage this is close to sufficient.

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 100% for the single 'key' parameter, whose schema description already lists ticker, 10-digit CIK, or entity name. The description's 'Accepts a ticker, CIK, or name' merely restates the schema, so baseline 3 applies with no added semantics such as ambiguity resolution or normalization rules.

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?

Names a specific resource (company relationship graph) and precisely defines what the edges are: other companies whose Form-4 filings name the same person(s), with concrete edge types (board interlock, multi-company executives, activist overlap). An agent can tell this apart from generic rollups like common_owner_rollup or influence_chain from the mechanism alone.

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 described edge types rather than stated: an agent can infer this is for finding interlocks, but the description never says when to prefer it over siblings such as common_owner_rollup, compare_entities, or influence_chain, nor states any exclusions or prerequisites.

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