Skip to main content
Glama

calls_transfer

Read-onlyIdempotent

Transfer the current phone call to a person on another number (e.g. 'let me put you through to a manager'). Only works on a live PHONE call, and only to a number the operator has pre-approved for this agent. Say one short sentence to the caller first ('connecting you now'), THEN call this. It rings the destination and returns when they pick up — which can take most of a minute — and only then do you leave the call. If nobody answers you are told so and are still on the line with the caller.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
toYesThe phone number to transfer the caller to, E.164 (e.g. '+15551234567'). Must be pre-approved for this agent.
call_idNoWhich call to transfer. Omit inside a live voice turn — it is taken from the call. Required over MCP.
in_workspaceNoRun this one call in this workspace id instead of the session's. Nothing is stored; other sessions are not affected.

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed1 schema field changed
    • addedInput schema / properties / in_workspace
      Added value: +{
      +  "description": "Run this one call in this workspace id instead of the session's. Nothing is stored; other sessions are not affected.",
      +  "type": "integer"
      +}
  2. Added

TDQS

A4.5/5.0
Behavior5/5

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

With annotations already covering readOnly/idempotent/open-world, the description adds substantial call-flow detail they cannot express: it rings the destination, blocks until pickup (up to 'most of a minute'), only then does the agent leave the call, and if nobody answers the agent is informed and remains on the line. The pre-approval prerequisite is also disclosed.

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?

Front-loads the action and example, then layers constraints, ordering, latency, and failure behavior in short clauses. Every sentence carries actionable information (timing, no-answer handling, speak-before-calling), with no redundant restatement of the name or schema.

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?

No output schema exists, yet the description explains the return semantics anyway (returns on pickup, reports no-answer while staying on the line) plus the latency an agent must plan around. For a 3-parameter live-call tool this leaves nothing material unstated.

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 description coverage is 100%, so `to`, `call_id`, and `in_workspace` are already documented with their formats and constraints. The description reinforces the pre-approval rule for the destination number but adds no syntax, range, or default information beyond the schema, so the baseline 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?

States a specific verb and resource ('Transfer the current phone call to a person on another number') and scopes it tightly ('Only works on a live PHONE call'). The phrase 'to a person on another number' implicitly separates it from agent_handoff (handing to an AI) and calls_make (originating a call), so an agent can route correctly 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.

Usage Guidelines4/5

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

Gives strong operative conditions: only on a live PHONE call, only to a pre-approved number, and the sequencing rule ('Say one short sentence to the caller first ... THEN call this'). It does not name a sibling alternative or state a when-not-to-use beyond the live-call/pre-approval limits, so it stops short of a full 5.

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

Try in Browser

Glama MCP Gateway

Add one secure layer between your agents and this server.