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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses the return fields, the constraint that only observed companies are returned, and explicitly states 'nothing is invented'—a strong guarantee against hallucinated data. However, it does not explicitly state that the operation is read-only (though 'search' implies it), nor does it mention ordering or potential rate limits. These are minor gaps given the tool's simplicity, but the description does a good job overall.

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 description is concise—three sentences with zero waste. It front-loads the core purpose and return fields, then provides usage guidance and a boundary constraint. Each sentence earns its place, and the structure is easy to scan. This is exemplary conciseness.

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 search tool with three well-documented parameters and no output schema, the description is nearly complete. It covers what the tool returns, when to use it, and its scope limitation. It does not mention result ordering (e.g., by first-seen date) or that empty results mean no history, but these are implied and not critical. The description is sufficient for an agent to call the tool correctly.

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 input schema already provides 100% description coverage for all three parameters (limit, query, offset), including defaults and examples. The description does not add any additional meaning or context about the parameters beyond what the schema already states. Since the schema does the heavy lifting, a baseline of 3 is appropriate; the description adds no extra value here.

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 clearly states the tool's function: searching companies previously observed by Revnuvo. It lists the exact fields returned (domain, first seen, observation count, tech stack, last scan time), which makes its purpose concrete and distinguishable from sibling tools like revnuvo_get_company (which likely fetches a single company) and revnuvo_search_signals (which searches signals). The phrase 'before querying deeper' explicitly positions it as a preliminary lookup.

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?

The description provides explicit guidance: 'Use this to check whether Revnuvo already has history for a company before querying deeper.' This tells the agent when to invoke this tool versus alternatives. It also clarifies the boundary condition: only observed companies are returned, so the agent can interpret empty results as no prior history. This is clear, actionable usage guidance.

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