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

With no annotations, the description carries the full transparency burden. It does disclose two behavioral facts beyond the operation: the need for an owner-issued temporary grant and that responses contain only masked metadata. It does not explain overwrite semantics, idempotency, side effects, or why only masked metadata is returned.

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, tightly worded sentence that front-loads the operation, states the precondition, and adds the response characteristic. There is no filler or repetition of schema details.

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?

For an 8-parameter write operation with no annotations, the description is too thin to be fully actionable. It omits guidance on optional parameters, the meaning of field_id versus field_key, and how this tool relates to swarme_vault_fill. The output schema may describe return values, but the missing usage and parameter context remains a significant gap.

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%, so the description must compensate for parameter meaning. It only clarifies vault_grant as an 'owner-issued temporary grant.' The other seven parameters—field_label, field_value, field_id, field_key, value_type, field_group, and sensitivity—receive no semantic explanation beyond their schema names.

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 states a specific action ('Create or update') and resource ('one Vault field'), and adds the key precondition of an 'owner-issued temporary grant.' This clearly distinguishes it from related tools like swarme_vault_fill, which imply bulk operations, and from read-oriented Vault tools.

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 the tool: when a single Vault field needs to be created or updated and the caller has a temporary grant. However, it does not explicitly state when not to use it or name alternatives such as swarme_vault_fill for multi-field scenarios.

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