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

With no annotations, the description carries the full burden and reasonably delivers: it discloses the pending-only constraint, the expiry behavior, the authentication requirement, and explicitly warns that start_login does NOT open this tool. It stops short of describing any side effects of generating a 'fresh' link (e.g., whether prior links are invalidated) or error behavior for already-approved confirmations.

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?

Three tightly scoped sentences deliver the core action, key constraints, and access prerequisite with no filler. The main function is front-loaded, and the access note is clearly separated yet still relevant. Every sentence 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?

For a one-parameter tool with no output schema, the description covers the essential inputs, constraints, and auth prerequisites. It does not describe the return value's shape or format, but the purpose implicitly tells the agent a link is returned. Minor gaps like side effects of 'fresh' links and error handling prevent a 5.

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 already documents the single 'id' parameter with a pattern and description 'Confirmation ID', giving 100% coverage. The description reinforces that the ID must refer to a pending confirmation but adds no format or syntax detail beyond the schema. Baseline 3 is appropriate.

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 verb ('Generate'), a precise resource ('fresh approval link'), and a crucial constraint ('Only works for pending confirmations'). This clearly differentiates it from siblings like get_confirmation, which presumably retrieves confirmation details rather than generating a link. The expiry inheritance note adds precision.

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 explicitly states the precondition ('pending confirmation') and gives clear auth instructions ('needs a Proof account', 'Authenticate this client... then call this tool again'). It also explicitly rules out start_login as a way to access this tool. It doesn't compare against all relevant alternatives, but the guidance is unambiguous about when it works.

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