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

The annotations already declare idempotency and a non-destructive profile, but the description adds a meaningful behavioral guarantee: it never overwrites values supplied by the applicant. That merge behavior is important context beyond the structured annotations, though no auth or rate-limit details are given.

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 tight sentences with the core action front-loaded and the key overwrite guarantee second. There is no redundant or filler language.

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 tool has a complete schema, annotations, and an output schema, so the description does not need to explain return values. It gives the core behavior and an important merge rule, though it could more explicitly position the tool against sibling hydration and preview tools.

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?

There is only one parameter, and the schema has 100% description coverage with a nested UUID wrapper already documented. The description does not mention applicationId or add syntax or constraints beyond the schema, so the baseline of 3 applies.

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 and clearly identifies both the source (equity intake) and target (an open application), so an agent can infer this is the equity-intake hydration path. It does not explicitly distinguish itself from sibling hydration tools such as banking_hydrate_from_cap_table or banking_hydrate_from_formation, keeping it short of a 5.

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 'onto an open application' implies the tool should be used when an application already exists and equity intake facts are available. However, it does not explicitly state when to choose this over the sibling preview or hydration tools, nor does it describe prerequisites or exclusions.

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