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

The description explicitly says 'Writes,' which is important since annotations only include openWorldHint=false and destructiveHint=false and do not convey that this is a mutation. It also exposes the behavioral distinction around close/reopen. It does not mention side effects, permissions, or reversibility, but the output schema and annotations cover some context.

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 short sentences with no filler. The core purpose and the critical exclusion are front-loaded, and every clause 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?

Given the complex nested schema and many cap_table siblings, the description gives enough orientation: what it updates, that it writes, and the main operation it does NOT perform. A minor gap is that the schema includes a status field while the description says the tool does not move rounds between open/closed, which could leave an agent unsure whether status can be edited here.

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 schema description coverage is 0%, so the description must compensate. It does add meaning by identifying the meaningful editable fields (name, target, valuation, dates) within the nested round object. However, it does not map these to the actual schema property names, nor explain the nested wrapper structure or the role of the required companyId.

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 ('Changes') and names the exact resource ('a funding round's own terms') plus the fields affected: name, target, valuation, dates. It explicitly draws a boundary against closing and reopening the round, which distinguishes it from the sibling tools cap_table_close_cap_table_round and cap_table_reopen_cap_table_round.

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 clearly states when to use the tool (modifying a round's own terms) and when not to use it (moving a round between open and closed). It even explains why closing is separate ('runs a conversion engine') and notes that reopening has its own dedicated call, giving the agent actionable routing guidance.

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