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

The annotations already provide readOnlyHint, idempotentHint, and destructiveHint=false, and the description adds meaningful non-persistence context: 'unsaved', 'no issued equity or saved investment'. This clarifies the operation has no side effects on the cap table or stored investments, which is valuable beyond the annotations.

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 a single, front-loaded sentence with no filler. Every clause adds a meaningful constraint: it calculates, it is an estimate, it is unsaved, and it explicitly excludes issued equity and saved investment.

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 annotations and output schema cover safety and return structure, and the description clearly frames the non-persistent nature of the operation. However, given the nested ModelInput schema with multiple optional fields and enum choices, the description does not provide enough modeling context or assumptions to help an agent configure a complex scenario confidently.

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 0%, and the description does not explain any of the key parameters such as cap_table_id, allocations, round_amount, round_valuation, pool_dilution_percent, or inclusion. The schema's titles and defaults carry most of the parameter-understanding burden; the description only provides a high-level domain clue.

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 uses a specific verb ('Calculate') and a specific resource ('cap-exposure estimate'), and it distinguishes itself by saying the estimate is unsaved and that there is no issued equity or saved investment. This clearly separates it from siblings like sparkclose.save_scenario or cap_table.simulate_raise.

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 phrase 'unsaved cap-exposure estimate' plus 'no issued equity or saved investment' gives clear context that this tool is for pre-save modeling scenarios. It does not explicitly name alternative tools or give direct 'use X instead' guidance, so it stops short of a 5.

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