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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description's 'Writes nothing' reinforces this. The description adds valuable behavioral context beyond annotations: it explains the return value behavior (available=false when no formation or no owners named). This is useful context that annotations don't provide.

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 with zero waste. It front-loads the core purpose, then adds the key behavioral note about writes and the edge case return value. Every sentence earns its place.

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?

The description is complete for a preview tool with a single parameter and full schema coverage. It covers the purpose, the non-destructive nature, and the edge case behavior. The output schema exists, so return values don't need to be explained in the description. It could potentially mention what the 'needs afterwards' output looks like, but the output schema likely covers that.

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 the single parameter (companyId as a UUID value wrapper). The description doesn't add parameter-specific details beyond what the schema provides, but with full coverage, the baseline 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 the tool's purpose: it reports which owners a company's formation would carry onto its cap table and what the cap table still needs afterwards. It uses a specific verb ('reports') and resource ('formation' to 'cap table'), and distinguishes itself from siblings like captable_hydrate_formation_carry by emphasizing it writes nothing and is a preview.

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 implies when to use this tool: when you want to preview the effect of a formation on the cap table without writing. It doesn't explicitly name alternatives or exclusions, but the 'Writes nothing' statement and the preview nature provide clear context. It could be improved by explicitly stating when to use captable_hydrate_formation_carry instead.

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