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

No annotations are provided, so the description must carry the full burden. It discloses a key limitation: 'History depth depends on your plan (free: 7 days).' It also specifies the output contents. However, it does not mention read-only status (implied by 'Retrieve'), rate limits, pagination behavior beyond the limit parameter, or any potential side effects. For a read tool, this is adequate but not exhaustive.

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 two sentences, front-loaded with the main purpose and contents, then a use case, then a plan caveat. There is no redundant phrasing; every sentence adds value. It is concise and well-structured.

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?

Given the tool's complexity (returns both observations and change events) and the absence of an output schema, the description gives a solid overview of the data returned and a caveat about plan-dependent depth. It doesn't detail the exact output structure or pagination beyond the limit parameter, but the schema covers the limit. Overall, it is sufficiently complete for an agent to call it 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?

Schema description coverage is 100% for both parameters (domain and limit). The description adds no additional parameter guidance beyond what the schema already provides, so it meets the baseline of 3.

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 retrieves the chronological observation history for a company, listing the specific data points (timestamp, source, confidence, state hash, change events). It is unambiguous about the resource and action, but does not explicitly differentiate from sibling tools like revnuvo_get_company_changes, which might overlap in returning change events.

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 a clear use case: 'Use it to answer how did this company's stack evolve?' This gives context for when to use the tool. However, it does not mention when not to use it or name alternative tools, so it lacks exclusions but still offers a clear contextual trigger.

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