Brreg MCP Server

search_subunits

Search for subunits in the Norwegian Business Registry by name, parent company, employee count, VAT status, or organization number.

Instructions

Search for subunits (business units) in the Norwegian Business Registry

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": "search_subunits"
  }
}

Input Schema

Name	Required	Description
`name`	No	Subunit name (free text, 1-180 characters)
`page`	No	Page number (default: 1)
`size`	No	Page size (default: 20)
`toEmployees`	No	Maximum number of employees
`fromEmployees`	No	Minimum number of employees
`parentCompany`	No	Parent company organization number
`registeredInVAT`	No	Whether registered in VAT register
`organizationNumber`	No	Comma-separated list of organization numbers

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.0.0Aug 2, 2026

TDQS

B3.2/5.0

Behavior2/5

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

No annotations are present, so the description must disclose behavioral traits. It merely states 'Search for subunits' without explaining pagination behavior, result format, filtering semantics, default limits, or potential errors. This leaves the agent with significant unknowns.

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?

The description is a single, front-loaded sentence that states the core function without unnecessary words. It earns its place.

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?

Given 8 controllable parameters, no output schema, and no annotations, the description is too terse. It fails to explain how filters combine, what the response contains, or how pagination behaves, leaving the agent under-informed for a moderately complex search tool.

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?

The input schema covers all 8 parameters with descriptions, so baseline is 3. The tool description adds no parameter-specific meaning, but the schema is already comprehensive.

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?

The description clearly identifies the action ('Search'), the resource ('subunits'/'business units'), and the scope ('Norwegian Business Registry'). It distinguishes from siblings like search_companies and get_subunit by specifying the subunit resource.

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 guidance is provided on when to use this tool versus alternatives such as search_companies or get_subunit. The description does not mention any exclusions, prerequisites, or preferred scenarios.

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

Deploy Server