hail

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by hail-hq

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Python

Hybrid

Get verification requirements

get_verification_requirements

Read-onlyIdempotent

Fetch the carrier’s verification requirements—required fields, documents, and address—before buying a phone number or registering for US SMS.

Instructions

Read what the carrier needs to verify the organization before it can buy a number. Call this when quote_numbers shows an offer with readiness == "verification_required". Read-only.

    ``country_code`` is ISO alpha-2 (for example ``"GB"``). ``number_type``
    is ``local``, ``mobile``, ``national`` or ``toll_free``.
    ``subject_type`` is required: ``person`` (the user) or ``business``
    (the user's company). Never guess it: ask the user "you or your
    company?". The result's ``subject_types`` lists what the carrier
    accepts. The organization may hold one verification of each. ``quote_id`` is the
    offer's ``quote_id`` from quote_numbers. It is required for
    ``purpose='number'``: the form is the one for that offer.

    ``purpose`` is ``number`` (default, to buy a number) or ``sms``.
    ``purpose='sms'`` registers the organization to text US numbers from a
    US number (country_code US, number_type local). Fees are charged from
    credit per step: when the details are submitted, when the carriers
    start their review, then monthly after approval. If the error says to pass
    ``number_id``, pass the ``id`` of one of the organization's US numbers
    from list_numbers.

    Returns ``required`` (false means no verification is needed and
    submit_verification would fail), ``fields`` (values to collect),
    ``documents`` (slots, each with ``options``), ``address_required``.
    A field of kind ``choices`` takes several of its ``options``: send
    their keys joined by commas (for example
    ``"CUSTOMER_CARE,DELIVERY_NOTIFICATION"``), between ``min_choices``
    and ``max_choices`` of them.
    A field with ``max_length`` takes at most that many characters,
    counted in UTF-16 code units (an emoji counts as 2); a longer value
    is refused (422).
    Skip any document slot whose ``needs_input`` is false: do not send it.

    Ask the USER for every value and every file. Never invent, guess or
    infer personal or company data. Never reuse data from another task.

    Errors come back as ``{"error": "<message>"}``.

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": {
      "country_code": "<country_code>",
      "number_type": "<number_type>",
      "subject_type": "<subject_type>"
    },
    "name": "get_verification_requirements"
  }
}

Input Schema

Name	Required	Default
`purpose`	No	number
`quote_id`	No
`number_id`	No
`number_type`	Yes
`country_code`	Yes
`subject_type`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed5 schema fields changedv0.30.0Oct 23, 2026

addedInput schema / properties / number_id

Added value: +{
+  "anyOf": [
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Number Id"
+}

removedInput schema / properties / provider

Removed value: -{
-  "anyOf": [
-    {
-      "type": "string"
-    },
-    {
-      "type": "null"
-    }
-  ],
-  "default": null,
-  "title": "Provider"
-}

addedInput schema / properties / quote_id

Added value: +{
+  "anyOf": [
+    {
+      "type": "string"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "default": null,
+  "title": "Quote Id"
+}

removedInput schema / properties / subject_type / default
```
Removed value: -"person"
```

changedInput schema / required

Previous value: -[
-  "country_code",
-  "number_type"
-]New value: +[
+  "country_code",
+  "number_type",
+  "subject_type"
+]

First observedv0.29.0Oct 21, 2026

TDQS

A5/5.0

Behavior5/5

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, but the description adds substantial workflow context: fees are charged per step for SMS, required=false means submit_verification would fail, and invalid field lengths are rejected with 422. It also warns never to invent or reuse personal data, which is important behavioral guidance beyond the annotations.

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?

Despite its length, the description is front-loaded with purpose and trigger condition, then proceeds through parameter meaning, return structure, validation rules, and data-handling constraints. Every section earns its place given six parameters with zero schema documentation and a multi-step verification workflow.

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?

An output schema exists, but the description still summarizes the key return fields an agent must act on: required, fields, documents, address_required, subject_types, and choices/min_choices/max_choices semantics. Combined with the detailed parameter and error guidance, nothing essential is missing.

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

Parameters5/5

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

Schema coverage is 0%, so the description carries the full burden and does so completely: country_code is ISO alpha-2, number_type lists the four accepted values, subject_type explains person vs business and requires asking the user, quote_id is required for purpose='number', number_id is the fallback for certain SMS errors, and purpose defaults to number.

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: read what the carrier needs to verify the organization before buying a number. It also names the sibling workflow condition from quote_numbers, so an agent can distinguish it from submit_verification, get_verification, and quote_numbers without opening another schema.

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

Usage Guidelines5/5

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

Explicitly says to call this when quote_numbers returns readiness == "verification_required", and distinguishes purpose='number' from purpose='sms'. It also gives the exact fallback for number_id and says to skip document slots with needs_input=false.

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