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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered. The description adds genuinely useful data-quality context ('amount where disclosed') and the shape of each edge (source URL + quoted snippet), which tells the agent results are evidence-backed and may be partially missing. It does not discuss pagination or limits.

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 dense sentence with the resource and the return contents front-loaded; no filler. Slightly long with the parenthetical role enumeration, 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 an output schema present, the description needn't detail return values, yet it usefully previews them. Given the single-parameter read-only nature of the tool, an agent has enough to invoke it correctly; only the sibling-routing gap remains.

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?

Only one parameter (company_id) and schema description coverage is 100%, so the schema fully documents it, including its provenance from vc_search_rounds. The description adds nothing about the parameter, which is the expected baseline when the schema does the heavy lifting.

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?

States a specific verb and resource ('List the investors named in a company's financing rounds') and even enumerates the returned edge attributes (role, amount, evidence). It is clear about what it does, but it never distinguishes itself from the very similar sibling vc_find_investors_for_company, leaving the agent to guess which to pick.

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?

There is no when-to-use guidance, no prerequisites, and no named alternative. The only workflow hint ('from vc_search_rounds') lives in the input schema, not the description, so the description itself offers no routing help among the many vc_* siblings.

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