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

The description discloses nonce expiry (30 minutes), single-use behavior, the one-X-account-to-one-Rokha-account constraint, and the Authorization header requirement. These add real behavioral context beyond the minimal 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?

Every sentence carries operational value: the action, the nonce flow, the browserless rationale, the linking benefit, the constraints, the prerequisite, and the auth requirement. It is dense but still reads clearly and front-loads the core action.

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?

With no output schema, the description adequately explains the return value ('one-time nonce') and how to use it. It also covers time limits, single-use semantics, the verification step, prerequisites, and auth, making it complete for an agent to invoke correctly.

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 are zero parameters, so the schema has no burden. The description's nonce protocol is an output/process detail rather than parameter semantics, so the baseline of 4 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 uses a specific verb ('Start') and resource ('headless X link') and clearly explains the tool's role: issuing a one-time nonce for proof of X account control. It also distinguishes this from x_link_verify, which is the follow-up verification step, so an agent can tell them apart.

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?

It explicitly says this is the agent path requiring no browser/OAuth, states the prerequisite (claim page handle first via page_claim), and tells the agent to call x_link_verify after posting. This gives both when-to-use and the expected next step.

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