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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds value beyond annotations by disclosing an edge-case behavior: the tool is 'unavailable rather than an error when there is nothing to carry.' This is a useful, non-obvious behavioral detail.

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?

Two concise sentences with no wasted words. The core purpose is front-loaded, and the second sentence adds meaningful behavioral information about read-only status and the no-content edge case.

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 and annotations covering the read-only/destructive profile, the description is largely complete. The only minor gap is that it does not explain what 'unavailable' means in practice, but this is a small ambiguity given the rest of the context.

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%, so the schema already documents companyId as a UUID value wrapper. The description adds no additional parameter meaning beyond implying the company context, so the baseline score of 3 is appropriate.

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 that the tool previews which cap-table stakeholders could be carried over as beneficial owners, with a specific resource and outcome. It differentiates from a write operation by explicitly saying 'without writing', but does not explicitly name or distinguish from sibling tools like banking_hydrate_from_cap_table or banking_preview_formation_hydration.

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 gives clear context: this is a read-only preview used to see potential carryover before actually writing. It does not explicitly state when-not-to-use it or name alternatives, but the 'without writing' and 'read-only' signals make the intended usage reasonably clear.

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