cancel_documentCancels a document still awaiting signatures, disabling signing links and notifying remaining signers by email. This action is irreversible, so confirm with the user first.
Cancels (voids) a document that is still being signed. Signing links stop working and the people still to act are told by e-mail. This cannot be undone; confirm with the user first.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | ||
| reason | Yes |
Changes observed during successful MCP inspections.
v0.1.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare destructiveHint=true, but the description adds concrete consequences the agent could not infer: signing links stop working, remaining signers are e-mailed, and the action cannot be undone. That is exactly the context needed to decide whether to proceed with an irreversible mutation.
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 short sentences, each doing distinct work: what it does, what happens as a result, and the irreversibility warning. The critical caution is front-loaded at the point of decision.
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 two-parameter destructive mutation with no output schema, the description covers side effects and irreversibility well, which is the high-risk part. The remaining gap is the undocumented required 'reason' parameter, which leaves the caller guessing at invocation specifics.
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 never mentions either parameter. The required 'reason' field in particular is unexplained — an agent gets no guidance on what it is for or how it is surfaced to recipients. Only 'the document' loosely implies 'id'.
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?
States a specific verb and resource ('Cancels (voids) a document') plus the precondition ('still being signed'), which cleanly separates it from send_document, send_reminder, and create_signing_link among the siblings. An agent can identify the operation without opening the 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?
Gives a clear eligibility condition ('still being signed') and an explicit operational instruction ('confirm with the user first'). It stops short of naming a specific alternative for documents already completed, so it is not a full when/when-not routing statement.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.