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

There are no annotations, so the description carries the full burden of behavioral disclosure. It only states that the output is 'rankings' and does not disclose whether the operation is read-only, what the ranking criteria are, what ordering is used, what data source/time period applies, or what a caller should expect in the response.

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 very short with no filler or repetition; every word contributes meaning. However, it is a grammatically awkward noun phrase rather than a clear sentence, and it omits even a simple verb like 'returns' or 'ranks.'

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 parameters, no annotations, and no output schema, the description is the only source of meaning, yet it is severely under-specified. It does not explain what the co-investment network is, what metric drives the ranking, whether the result is a list or single value, or how this differs from get_cornerstone_ranking.

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 tool has zero parameters and an empty input schema, so the parameter dimension has a baseline of 4. The description adds useful context about the subject matter, which is sufficient given that there are no parameters to document.

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 a concrete resource—'cornerstone investor co-investment network rankings'—and is not a tautology. It clearly implies that the tool returns a ranking, but it is a noun phrase rather than a verb statement, and it does not differentiate this from closely related siblings like get_cornerstone_ranking or get_buyback_ranking.

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?

No guidance is provided about when to use this tool versus alternatives. The description does not mention the closest sibling tools, typical use cases, or any conditions that would select this tool over another ranking tool.

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