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

Despite annotations covering safety (idempotent, non-destructive), the description adds material behavior: the payload is a full replace (not a patch), an email change resets `emailVerified` to false and re-sends a code to the NEW address, and the terminal `notEditable` state past `draft`. It also discloses the return shape and how to request JSON.

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?

Front-loaded purpose followed by clearly labeled When / Before you call / Returns / On error sections. Every block carries distinct decision-relevant content with no filler, and the format guidance is compressed into one clause.

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?

An output schema exists, yet the description still notes the return is a `StatusView` matching `get_status` and how to get JSON. With mutation semantics, an irreversible verification reset, and multiple enumerated error states all covered, nothing needed to call it correctly is missing.

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 coverage is 100% and the schema already states 'replaces the current payload wholesale' and 'resets verification and issues a new code,' so the description largely restates those. It does add operational value the schema lacks: read current values from `get_status` before sending a full payload, and warn the founder about the email change.

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 opening sentence gives a specific verb (update), resource (application), and scope constraint (payload and/or contact email, only while in `draft`). It further pins the boundary by referencing the siblings it sits between (`create_application`, `verify_email`), so an agent can distinguish it from them without opening a schema.

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?

Explicit '**When:**' section names the two triggering situations (fixing a mistake after `create_application`, changing the email) and the lifecycle window (before `verify_email`). Alternatives are routed by name (`get_status` for reading, `create_application` for the initial write), and failure-mode guidance is provided.

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