hail

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by hail-hq

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Python

Hybrid

List calls

list_calls

Read-onlyIdempotent

List recent calls in your organization, newest first.

Instructions

List recent calls in your organization, newest first.

    Cursor-paginated: pass the previous response's ``next_cursor``
    to fetch the next page. ``status`` (one of queued, dialing,
    ringing, in_progress, completed, failed, busy, no_answer,
    canceled) and ``to`` (E.164) are optional server-side filters.

    Returns a dict ``{"items": [...], "next_cursor": <str|None>}``.

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_calls"
  }
}

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/openWorld=false, so the safety profile is covered. The description adds real context beyond them: newest-first ordering, org-wide visibility, server-side filtering, and cursor-pagination behavior. It omits rate limits and the effect of the default limit, which keeps it from a 5.

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?

Three tight paragraphs, front-loaded with purpose then pagination then return shape. Every sentence carries information the schema does not; only minor RST double-backtick artifacts add noise.

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?

An output schema exists, so restating the return shape is redundant but harmless. For a 4-param read tool with strong annotations, the definition is nearly sufficient; the missing piece is any guidance on `limit` (default 50, max value) and on how pagination terminates when next_cursor is null.

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 parameter meaning, and it largely does: it enumerates all valid status values (the schema has no enum), specifies E.164 for `to`, and explains that `cursor` comes from the previous response's next_cursor, none of which is in the schema. The `limit` parameter is never mentioned, leaving one of four parameters undocumented anywhere.

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: 'List recent calls in your organization, newest first.' The ordering guarantee and org-wide scope make the operation unambiguous. It does not explicitly route the agent away from get_call/list_sms siblings, but the list-vs-get distinction is clear from the content.

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 mechanics are given (pass next_cursor to page, filters are optional and server-side), which implies the pagination workflow, but there is no explicit statement of when to prefer this over get_call or when-not to use it. The agent must infer routing from the tool names.

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