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

Annotations already indicate destructiveHint=true, so the description builds on that by adding that the investor signing token is returned only once, and explains the signer ordering and PDF rendering. This adds meaningful behavioral context 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 two sentences, front-loaded with the primary purpose, and efficiently includes the token-once caveat and signer order without unnecessary filler.

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 tool's complexity (11 params, low schema coverage), the description provides a high-level workflow but leaves a significant gap in parameter usage and data contract needed to invoke it correctly. The output schema exists, so return values are covered, but the input side is under-specified.

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?

With only 27% schema description coverage, the description should compensate for the 11 parameters. It gives some clue about signer ordering (company order 1, investor order 2) but does not explain required parameters like founderUserId or companyName, nor optional but important ones like safeAgreementId or valuationCap.

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 'opens a two-party SAFE signing envelope' with a specific verb and resource. It distinguishes itself from generic signature tools by specifying 'SAFE' and 'cap-table-supplied data', and mentions the prerequisite fetch via company.GetSafeAgreement.

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 provides clear context: the tool is used when the caller has already fetched the SAFE agreement via company.GetSafeAgreement. It implies a specific workflow but does not explicitly mention when not to use it or alternatives like signature_create_envelope, so it stops short of full exclusion guidance.

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