Change the admin password on a DrayTek Vigor 3912S router by providing current and new passwords. Requires confirmation to complete the write operation.
Change the admin password (write — requires confirmation)
| Name | Required | Description | Default |
|---|---|---|---|
| new | Yes | ||
| old | Yes | ||
| user_code | No | ||
| acknowledge | No | ||
| confirm_token | No | ||
| confirmation_id | No |
Changes observed during successful MCP inspections.
v0.6.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of behavioral disclosure. It does state that it is a write operation and requires confirmation, which is a critical behavioral trait. However, it does not explain the confirmation flow (e.g., how confirm_token/confirmation_id are obtained), whether the old password must match, or any consequences like irreversibility or session invalidation.
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 concise sentence with no fluff, and the core purpose is front-loaded. It is efficient, though the brevity borders on under-specification, which is already penalized in contextual completeness.
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?
Given 6 parameters, 0% schema coverage, no annotations, and no output schema, this description is grossly inadequate. It fails to explain the confirmation prerequisite (despite claiming it), the meaning of optional fields, or any error/return behavior. An agent would have to guess much of the required input structure.
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%, and the description adds no meaning to any of the 6 parameters. It does not clarify that 'old' is the current password, nor does it explain the optional parameters (user_code, acknowledge, confirm_token, confirmation_id). The tool name and schema field names alone are insufficient for an agent to correctly construct valid calls.
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 the specific action ('Change the admin password') and the parenthetical clarifies it is a write operation requiring confirmation. This clearly distinguishes it from the many read-only status tools in the sibling list and leaves no ambiguity about the tool's purpose.
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 gives no guidance on when to use this tool versus alternatives. While there is no direct password-altering sibling, related user management tools exist (user_account, user_edit), and the description does not explain this is the admin-specific password change. No prerequisites or exclusions are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.