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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the description's additional behavior details are valuable. It discloses that results are precomputed matcher output, lists exactly which fields are returned verbatim, and explains the NOT_COVERED sentinel with population count.

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 sentences each carry distinct and necessary information: what is returned, what NOT_COVERED means, and which sibling tool to use instead. The main functional statement is front-loaded, with no filler or repetition.

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?

Since there is no output schema, the description carries the full burden of explaining return values. It enumerates the returned fields, including reasons, blockers, why_now, comparable transactions, score, confidence, and model version, and explains the special NOT_COVERED case. Nothing an agent needs to interpret the result is missing.

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?

The schema already documents dfx_id fully, including the allowed namespaces, and limit has default/min/max constraints. The description reinforces the id format but adds nothing about the limit parameter or how it shapes results. It is adequate but does not meaningfully compensate for the 50% schema coverage gap.

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 states a specific verb and resource: it returns computed buyer_for_company matches from the private equity matcher for one company, with exact accepted id namespaces (dfx:pe:, dfx:isi:, dfx:vc:). The title further clarifies the direction of the match — PE firms that could buy this company — making it easy to distinguish from reverse or adjacent search tools.

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 explicitly gives an alternative: 'For sponsors, family offices and capital providers as well, use find_capital_for_opportunity.' It also clarifies when the result is NOT_COVERED: 'that means DFX has not computed buyers for it, never that no buyer exists,' preventing a critical misinterpretation.

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