hail

Official

by hail-hq

Overview Schema Source Related Servers Discussions Admin

Python

Hybrid

List text messages

list_sms

Read-onlyIdempotent

Page through recent SMS messages for your organization.

Instructions

Page through recent SMS messages for your organization.

    ``status`` filters to one of: queued, sent, delivered, failed,
    undelivered, received. ``to`` filters to messages sent to a
    specific E.164 number. Paginate with the returned
    ``next_cursor``.

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_sms"
  }
}

Input Schema

Name	Required	Description	Default
`to`	No
`limit`	No
`cursor`	No
`status`	No

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.29.0Oct 21, 2026

TDQS

A3.9/5.0

Behavior4/5

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds real behavioral detail beyond that: the valid status values, E.164 formatting for `to`, and cursor-based pagination via `next_cursor`. It stops short of defining what "recent" means or any result window.

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?

Four short sentences, each carrying distinct information (scope, status values, to-format, pagination), with the core purpose front-loaded. No filler or repetition of schema fields.

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

Completeness4/5

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

With an output schema present, the description needn't explain return shapes, and it correctly focuses on filtering and pagination. The remaining gaps — undefined "recent" window and unstated `limit` behavior — are small but real for a paginated listing tool.

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

Parameters4/5

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

Schema coverage is 0%, so the description must carry the load, and it does for three of four parameters: `status` gets an explicit value list, `to` gets E.164 format semantics, and `cursor` is tied to the returned `next_cursor`. Only `limit` is left undocumented, which is a minor gap against the schema default of 50.

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?

States a specific verb and resource with scope: paging through recent SMS messages for the organization. The verb distinguishes it from get_sms (single retrieval) and send_sms (write), even though those siblings aren't named explicitly.

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

Usage Guidelines3/5

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

Usage is implied by the description of filters and pagination, giving the agent a clear picture of the listing use case. However, it never states when to prefer this over get_sms for a known message or how to narrow results beyond the three filters.

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