EngageLab Agent Email MCP Server

Official

Overview Schema Source Related Servers Discussions Admin

list_threads

Retrieve conversation threads grouped by counterpart to review email exchanges. Filter by mailbox, keyword, or page to locate specific discussions.

Instructions

List conversation threads. A thread groups messages exchanged with the same counterpart.

Tool call template

This tool declares no required parameters. Add optional parameters from the input schema as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {},
    "name": "list_threads"
  }
}

Input Schema

Name	Required	Description
`pageNo`	No	Page number, starts at 1
`keyword`	No	Search keyword
`pageSize`	No	Page size
`mailboxId`	No	Filter by mailbox ID

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Sep 1, 2026

TDQS

C2.9/5.0

Behavior2/5

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

With no annotations, the description carries the full behavioral burden, but it only says 'List conversation threads' and defines a thread. It does not disclose pagination behavior, ordering, result shape, or any access constraints, leaving important operational details unspecified.

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

Conciseness4/5

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

Two short sentences with no filler; the primary action is front-loaded and the defining clause is immediately useful. It could be slightly more informative, but as written it is appropriately compact.

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

Completeness2/5

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

The tool has no output schema and no annotations, yet the description does not explain what a successful response contains, how pagination works, or how filters combine. While the parameters are schema-documented, an agent is left without enough operational context to fully anticipate the tool's behavior.

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 the parameter meanings are already documented in the input schema. The description adds no additional semantic detail beyond the schema, matching the baseline for full coverage.

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

Purpose4/5

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

The description states a clear verb ('List') and resource ('conversation threads'), and adds a useful definition of what a thread is. It does not explicitly differentiate itself from siblings like get_thread or list_thread_messages, but the intent is unambiguous.

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

Usage Guidelines2/5

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

No usage context is provided: the description does not say when to choose list_threads over list_thread_messages, get_thread, or list_inbound_messages. It also fails to mention whether filtering by mailbox or keyword is the intended way to narrow results.

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

Deploy Server