CallMCP — Phone Call MCP Server

Pause Call Campaign

pause_call_campaign

DestructiveIdempotent

Pause an outbound call campaign. Stops its queued and scheduled calls and cancels pending call attempts; a call already in progress may finish. Leads are kept and the campaign can be resumed later with launch_call_campaign. Needs campaign_id, the calls:write scope and an admin role in the business. Pausing an already paused campaign changes nothing.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "campaign_id": "<campaign_id>"
    },
    "name": "pause_call_campaign"
  }
}

Input Schema

Name	Required	Description	Default
`business_id`	No	Business ID. Required when the token can reach more than one business.
`campaign_id`	Yes	The call campaign, from list_campaigns.

Output Schema

Name	Required	Description
`error`	No	Present when success is false
`action`	No
`queued`	No
`success`	Yes	Whether the tool completed successfully
`campaign_id`	No
`paused_jobs`	No
`reset_leads`	No
`sequence_id`	No
`cancelled_attempts`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedNov 12, 2026

TDQS

A4.5/5.0

Behavior5/5

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

Annotations only declare destructive=true and idempotent=true; the description supplies the substance behind them — queued/scheduled calls stop, pending attempts are cancelled, an in-progress call may finish, leads are retained, and the campaign is resumable. It also discloses the required calls:write scope and admin role, which annotations cannot express.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The effect of the call is front-loaded in the first two sentences, followed by state preservation, permissions, and idempotency. Every sentence carries distinct information with no repetition or filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a destructive mutation tool with an output schema, the description covers side effects, what survives, resumability, auth prerequisites, and idempotent behavior — everything an agent needs before invoking it. No material gap remains.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and both parameters are documented in the schema, including the business_id multi-tenant condition. The description confirms campaign_id is required but adds no format or sourcing detail beyond what the schema already states, so the baseline of 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb and resource ('Pause an outbound call campaign') and immediately distinguishes it from the resume path by naming launch_call_campaign. An agent can tell this apart from launch/email-campaign siblings without inspecting any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives a clear usage context (halting queued and scheduled calls) and explicitly routes the agent to launch_call_campaign for resuming, plus notes that pausing an already paused campaign is a no-op. It stops short of stating when-not-to-use (e.g., a permanent cancellation path), but the guidance is well beyond implied.

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

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