companies-house-screening-mcp
This server lets you screen and inspect UK companies using Companies House data through MCP tools.
Batch-screen up to 50 companies at once, returning one row per company with signal codes and clearly labelled unresolved or skipped entries.
Get a one-call company snapshot combining profile, officers, charges, insolvency, and derived signals.
Search for companies by name or number and get ranked candidates with disambiguation guidance.
Look up company profiles, officers, filing history, charges, persons with significant control, insolvency history, and officer appointments.
Find officers by name and trace their appointments across companies for conflict-of-interest checks.
Use factual signals such as accounts overdue, outstanding charges, insolvency history, or recent incorporation rather than risk scores.
Verify invoices or suppliers by checking active status, registered office address, age, and warning signals.
Retrieve untouched raw Companies House payloads when verbose mode is enabled.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type
@followed by the MCP server name and your instructions, e.g., "@companies-house-screening-mcpScreen these companies: Acme Ltd, Beta Ltd, Gamma Ltd"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
companies-house-screening-mcp
Turn a list of UK companies into a register-checking worksheet in your AI assistant: registered details, filing observations, charges, and entries that need human follow-up.
Free, MIT-licensed source. Read-only access to Companies House. Your AI client may have its own account requirements or charges.
Try a business workflow
Paste this into your assistant after connecting the server:
Screen companies 04138203 and 00000006. Return one row per input with legal name, registered status, factual signals, sections checked, missing sections and data freshness. Keep unresolved and not-screened entries visible. Do not assign a risk score or call any company safe. Explain which records need human follow-up and why.
The server returns structured facts; your assistant formats the worksheet. The executed supplier example shows the actual response from recorded public-register fixtures. Its data is a dated example, not a current assessment of those companies.
First-video setup and script · Sample list · Business prompts and filming scripts · Setup walkthrough
Two more prompts:
Check company 04138203 against the legal name and registered-office address I supply from an invoice. Show matches, differences and unknowns. Do not treat a match as proof that the invoice or bank details are authentic.
Get the filing history for company 04138203. Summarise filings since the date I give you, fetching further pages as needed. Distinguish filing dates from the period covered. Do not claim to have read the filed documents.
Related MCP server: Companies House MCP Server
Connect
There is no public endpoint advertised by this project. Use a local server with your own free Companies House API key, or connect to an instance you or your organisation operates. A placeholder URL is not a working service.
Local: your own key, no hosting
Install Node.js 22 or newer and an MCP client that supports local stdio servers.
Register at the Companies House developer portal, create a Live application and a REST API key.
Add this configuration to your client's MCP server settings, replace the key, and restart or reconnect the client:
{
"mcpServers": {
"companies-house": {
"command": "npx",
"args": ["-y", "companies-house-screening-mcp@latest"],
"env": { "COMPANIES_HOUSE_API_KEY": "your_key" }
}
}
}On Windows, some clients require npx.cmd as the command. See setup and troubleshooting for client configuration, success checks, Docker and Windows details. Keep keys out of screenshots and source control.
Hosted: an operator supplies a URL
An operator can deploy to Cloudflare Workers or a single Node host using the deployment guide. Users then connect to its actual HTTPS MCP URL. For example, in Claude Code:
claude mcp add --transport http companies-house https://YOUR-HOST/mcpThe shared key has a finite budget; a public service is not unlimited. Rate limits explains fair shares, partial batches and bring-your-own-key support. Read operating a public deployment before sharing an endpoint. This repository does not promise hosted availability or free hosting.
Read results correctly
Signals are observations, not a credit rating, fraud verdict or onboarding approval.
Registered status
activedoes not establish current trading, solvency, invoice authenticity or bank-account ownership.An empty signal list is not a clean bill of health. Check each row's
sections_included,sections_unavailableandmeta.Snapshots fetch one officer page.
officers.paginationdescribes that page before filtering to active entries; counts describe the whole register. Useget_officerspagination for the remaining records. Screening exposesofficers_paginationwhen requested.Outstanding and partially satisfied charges are separate observations. Registration does not reveal the current debt balance; satisfaction records can lag repayment.
Check
meta.age_secondsandmeta.stale. Profiles, charges and insolvency have a 24-hour cache TTL by default. A hosted caller cannot force a refresh through a tool argument; the operator can disable caching.Company names can be ambiguous. Confirm the intended legal entity. Number validation rejects names but cannot detect every plausible company number invented by an AI.
This covers entities on the UK register, not every UK business. No result for a sole trader is not evidence of wrongdoing.
Filing history describes filings. This server does not download or analyse account PDFs, submit filings, or schedule company watches.
Tools
Tool | Purpose |
| Find candidates and resolve a name to a company number. |
| Search officer identities; a shared name alone does not prove identity. |
| Registered profile and filing due dates. |
| Paginated current and resigned officer records. |
| Paginated filing metadata, filterable by category. |
| Registered security, holders and satisfaction categories. |
| Registered persons with significant control. |
| Recorded insolvency cases and practitioners. |
| Paginated appointments associated with an officer ID. |
| Profile, officer page, charges and insolvency with factual signals. |
| Up to 50 names or numbers, with coverage and unresolved/skipped entries. |
Generated tool reference · Executed recipes · MCP capabilities
Engineering and evidence
The client handles timeouts, retryable failures, caching and request budgets. Projections simplify upstream responses; deterministic rules derive signals. Composite tools fetch the profile first, avoiding extra requests for an invalid company, then fetch the other sections concurrently.
The tradeoff is explicit: an officer summary costs one upstream request, while full officer coverage requires pagination. The output exposes that boundary instead of implying the summary is exhaustive.
Tool references are generated from a running MCP server and recipes execute against recorded fixtures. CI checks those generated files for drift. Handwritten guidance and external service details still require review.
Node tests cover the domain, transports and failure handling; Workers tests execute inside workerd. CI runs Node checks on Linux and Windows. Release workflows verify the package and publish npm/container provenance. Architecture decisions document the choices, including partial results and runtime portability.
The tool-selection eval measures first-call choice, arguments and grounding across 58 cases. It does not establish the accuracy of a complete business report. Historical measurements and their provenance limitations are documented there; new runs record source and execution metadata.
Related project
companies-house-mcp by aicayzer is an alternative worth evaluating, particularly for broader API or document access. Check its current documentation for capabilities. This project's focus is batch screening, composite summaries, explicit coverage and tool-selection evaluation.
Configuration
Only one variable is required.
Variable | Default | Notes |
| — | Required. Create a REST API key at the developer portal. Not a streaming key. |
|
| Override for a proxy. |
|
| Requests per window. Lower it if the key is shared with another process. |
|
| Five minutes. |
|
| Fraction of the budget this process will use. |
|
| |
| platform cache dir | Respects |
|
| Per request. |
|
| Retries after the first attempt. |
|
|
|
| — | Absolute path to a |
Development and verification
npm ci
npm run typecheck
npm run build
npm run docs:check
npm run test:coverage
npm run test:workers
npm run release:checkBuild before tests so the compiled stdio entry-point tests run. No API key is required for the offline suites. After changing tool schemas or recipe prose in scripts/generate-recipes.ts, run npm run docs:generate and commit the generated changes.
For live validation, copy .env.example to .env, supply a Companies House REST key and run npm run test:live. Scheduled CI runs this only when its secret is configured. Model evaluations require a separately billed provider key; see eval instructions.
The published server does not automatically read a working-directory .env. Set CH_ENV_FILE to an absolute path if needed. Fixture recording and observability cover maintenance.
Licence and data reuse
Source code: MIT, including commercial use subject to its notice requirements.
Companies House data is separate from the source-code licence. The Open Government Licence v3.0 applies to eligible public-sector information, subject to its exclusions. Personal data is excluded from OGL licensing; public availability does not remove applicable data-protection duties. See the National Archives' exceptions.
When reusing OGL-covered information, include:
Contains public sector information licensed under the Open Government Licence v3.0.
The response label OGL-v3.0 does not grant blanket reuse rights over every returned field. This project is not affiliated with or endorsed by Companies House.
Available Tools
11 toolscompany_snapshotCompany snapshotARead-onlyIdempotent
Everything worth knowing about one company in a single call: profile, serving officers, outstanding charges and insolvency cases, plus a list of signals read off the register. Use this instead of calling get_company, get_officers, get_charges and get_insolvency separately — it costs one round trip of yours rather than four, and it fills in the sections that Companies House reports as 404 when a company simply has none. The signals are facts, not a rating: this server does not score companies, and an empty signal list means nothing on the list was found rather than that the company is sound. Check sections_included before drawing a conclusion from an absent signal.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. | |
| include_charges | No | Include charges. On by default. | |
| include_officers | No | Include serving officers. On by default; turn it off to save one request per company. | |
| include_insolvency | No | Include insolvency cases. On by default. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| name | Yes | |
| status | No | |
| charges | No | |
| signals | Yes | |
| accounts | Yes | |
| officers | No | |
| age_years | No | |
| sic_codes | Yes | |
| insolvency | No | |
| dissolved_on | No | |
| company_number | Yes | |
| incorporated_on | No | |
| type_description | No | |
| sections_included | Yes | Which sections were fetched. Signals can only reflect the sections listed here. |
| sections_unavailable | Yes | Sections that failed. The snapshot is still returned; treat those signals as unknown. |
| confirmation_statement | Yes | |
| registered_office_address | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive. The description adds valuable behavior: signals are facts not ratings, empty signal list means nothing found rather than soundness, incomplete 404 sections are filled, and the caller must check sections_included before concluding absence. This goes beyond the structured hints without contradicting them.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is dense but well organized: it opens with the core value proposition, then gives the comparison to siblings, then the interpretation caveat, then the sections_included caution. Every sentence adds information and none are redundant with the schema or annotations.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the output schema exists and annotations carry the safety profile, the description covers what an agent needs to invoke correctly: when to use it, what it returns at a high level, how to interpret empty signals, and how to control size/cost via parameters. Nothing critical is missing for a read-only aggregation tool.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents all five parameters well. The description adds context beyond the schema, particularly the round-trip cost implication of include_officers and the caution about verbose payload size. It does not re-describe every parameter, which is appropriate given full schema coverage.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description uses a strong verb phrase ('Everything worth knowing about one company in a single call') and enumerates the exact resources covered: profile, serving officers, outstanding charges, insolvency cases, and signal list. It also explicitly contrasts with sibling calls (get_company, get_officers, get_charges, get_insolvency), making differentiation unmistakable.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It explicitly states when to use this tool instead of the four separate sibling tools, noting the round-trip advantage and the fact that it fills in sections that Companies House reports as 404. It also warns against misinterpreting empty signal lists and directs users to check sections_included, and implicitly routes name-only lookups to find_company via the schema description.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
find_companyFind a companyARead-onlyIdempotent
Search Companies House for a UK company by name, trading name or number. Start here whenever you have a name rather than a number, because every other tool in this server needs the number. Returns a shortlist with status, type and incorporation date so that companies with similar names can be told apart. When disambiguation_needed is true, ask the user which one they meant instead of taking the first result — dozens of live companies share a name, and picking the wrong one produces a confident answer about the wrong business.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | Company name, partial name, or company number. | |
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| start_index | No | Zero-based offset into the full result set. Use pagination.has_more to decide. | |
| items_per_page | No | How many records to return. Defaults to the API default; the maximum is 100. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| query | Yes | |
| companies | Yes | |
| pagination | Yes | Where this page sits in the full result set. |
| exact_name_match | No | Company number whose name matches the query exactly. Absent if none did. |
| disambiguation_needed | Yes | More than one candidate and no exact name match. Ask the user which one they meant. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the tool as readOnly, openWorld, idempotent, and non-destructive, so the bar for additional disclosure is met. The description goes beyond annotations by explaining the shortlist contents, the disambiguation flag, and the real risk of confidently answering about the wrong company when names collide. This is valuable behavioral context not present in the schema or annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is three sentences, each earning its place: the first states the core function, the second gives routing guidance, and the third warns about a critical failure mode. It is front-loaded with the action and resource, and there is no filler or restatement of the tool name.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only search tool with a 100%-covered schema, an output schema, and strong annotations, the description is complete. It covers purpose, when to use it, what results look like, and how to handle ambiguity. Nothing needed for correct invocation is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema fully documents all four parameters. The description adds no new parameter semantics beyond what the schema already provides, though it does reinforce that the query can be a name, trading name, or number, which matches the schema. Baseline 3 is appropriate because the schema carries the full burden.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific action ('Search Companies House for a UK company'), specific inputs (name, trading name or number), and a specific output (shortlist with status, type, incorporation date). It distinguishes this tool from siblings by explicitly positioning it as the starting point when you have a name rather than a number, which differentiates it from get_company and similar number-based tools.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives direct usage guidance: use this tool whenever you have a name rather than a number, because every other tool in the server needs the number. It also gives a concrete behavioral rule: when disambiguation_needed is true, ask the user which company they meant rather than blindly taking the first result.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
find_officerFind an officerARead-onlyIdempotent
Search Companies House for a company officer — a director, secretary or LLP member — by name. Returns candidate officer IDs with how many appointments each holds. Use it when you have a person and want the companies they are involved in; feed the officer_id to get_officer_appointments. Officer records are per-appointment-identity rather than per-person, so a common name returns many candidates and the appointment count and date of birth are usually what separates them.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | The officer's name. | |
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| start_index | No | Zero-based offset into the full result set. Use pagination.has_more to decide. | |
| items_per_page | No | How many records to return. Defaults to the API default; the maximum is 100. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| query | Yes | |
| officers | Yes | |
| pagination | Yes | Where this page sits in the full result set. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond the read-only/idempotent annotations, the description discloses a key behavioral quirk: officer records are per-appointment-identity rather than per-person, so common names return many candidates and appointment count plus date of birth separate them. This is exactly the kind of caveat an agent needs before invoking or interpreting results.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Purpose is front-loaded in the opening sentence, followed by return values, usage guidance, and a caveat. Every sentence adds useful information and there is no padding or redundancy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Covers what the tool does, when to use it, what it returns, a key data-model caveat, and the downstream tool to call next. With a complete input schema and an output schema present, nothing essential is missing for correct selection and invocation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema already describes all four parameters with 100% coverage, so the baseline is 3. The description adds no param-specific detail beyond 'by name', which the schema already conveys; it relies on the schema for parameter meaning.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States the exact operation — 'Search Companies House for a company officer by name' — and scopes it to directors, secretaries, and LLP members. It also clarifies the output is candidate officer IDs with appointment counts, which distinguishes it from company search and officer-appointment retrieval tools.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Gives an explicit usage condition: use it when you have a person and want the companies they are involved in, and names get_officer_appointments as the next step. It does not spell out when-not-to-use it versus siblings like get_officers, but the context is otherwise clear.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_chargesGet chargesARead-onlyIdempotent
Secured debt registered against a company: who holds each charge, what it covers, when it was created and whether it has been satisfied. outstanding_count is derived here because Companies House reports what has been settled but never what has not, and outstanding charges are the number that matters when screening a supplier or a debtor. A floating charge covering all assets is worth reading closely. Needs a company number.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| charges | Yes | |
| total_count | Yes | |
| company_number | Yes | |
| satisfied_count | Yes | |
| outstanding_count | Yes | Derived: total minus satisfied and part-satisfied. |
| part_satisfied_count | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
While annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, the description adds meaningful behavioral context: outstanding_count is derived because Companies House does not report unsettled charges, and floating charges deserve closer scrutiny. This goes beyond the structured annotations without contradicting them.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is four sentences and each contributes value: what the tool returns, an important derived-field nuance, a risk heuristic, and an input requirement. It is appropriately front-loaded with the core definition, though slightly longer than strictly necessary.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the output schema exists and the tool is a read-only retrieval operation, the description covers the essential context: what charges are, why the derived field matters, a caution about floating charges, and the required identifier. Minor gaps like pagination are not critical given the output schema.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already fully documents company_number and verbose. The description adds no new parameter-specific detail beyond restating that a company number is needed, which the schema already covers. A baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly identifies the resource (secured debt/charges registered against a company) and the specific attributes returned: holder, coverage, creation date, and satisfaction status. This distinguishes it from sibling tools like get_company or get_psc, which address different company data domains.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives a concrete use case ('when screening a supplier or a debtor') and states the required input ('Needs a company number'). It does not explicitly call out alternatives or when not to use the tool, but the schema does point to find_company when only a company name is available.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_companyGet a company profileARead-onlyIdempotent
The registered profile for one UK company: legal name, status, type, incorporation date, registered office, SIC codes, and the accounts and confirmation statement due dates. Also returns derived flags that Companies House does not provide — whether filings are overdue, whether the company holds charges or has insolvency history, and whether it was incorporated within the last year. Use it to verify a company is real and active before relying on it. Needs a company number; call find_company first if you only have a name.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| name | Yes | |
| type | No | |
| flags | Yes | Derived risk signals. Each one is computed here, not returned by Companies House. |
| status | No | |
| accounts | Yes | |
| age_years | No | Whole years since incorporation. |
| sic_codes | Yes | Standard Industrial Classification codes for the trade. |
| dissolved_on | No | |
| jurisdiction | No | |
| status_detail | No | |
| company_number | Yes | |
| incorporated_on | No | |
| type_description | No | |
| confirmation_statement | Yes | |
| registered_office_address | No | |
| registered_office_in_dispute | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish that the tool is read-only, idempotent, and non-destructive. The description adds valuable behavioral context beyond annotations: it returns derived flags that Companies House itself does not provide, such as overdue indicators, charges/insolvency history presence, and recent incorporation. It also repeats the input constraint that only a company number is accepted. No contradiction with annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is longer than minimal but every sentence earns its place: first the returned data inventory, then the derived flags, then the intended use case and prerequisite. It is front-loaded with the resource and scope, and there is no filler or tautology.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the read-only annotations, complete parameter schema, and existing output schema, the description covers everything an agent needs to select and invoke this tool correctly: what it returns, what derived flags it adds, when to use it, and how to handle a name-only input. No critical behavioral or prerequisite information is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already fully documents both company_number and verbose. The tool description reinforces the 'do not pass a name' caveat and the find_company prerequisite, but it does not add meaningful parameter-level semantics beyond what the input schema already provides. Baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb and resource: it returns the registered profile for one UK company, and enumerates the exact fields included (legal name, status, type, incorporation date, registered office, SIC codes, due dates). It also distinguishes the tool from find_company by clarifying that get_company needs a company number and does not accept a name.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description explicitly says to use this tool to verify a company is real and active before relying on it, and directs agents to call find_company first if only a name is available. It does not explicitly mention when to prefer related sibling tools like get_charges or get_insolvency, but it does clarify that it returns only derived flags about those topics rather than full details.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_filing_historyGet filing historyARead-onlyIdempotent
What a company has filed and when — accounts, confirmation statements, officer changes, mortgages, address changes. Use it to judge whether a company is filing on time, to see when accounts were last made up, or to watch a competitor's filing cadence. Descriptions come back as Companies House template keys such as accounts-with-accounts-type-small, with their values alongside; the key is readable enough to interpret and is not translated here because a partial translation would render some filings wrongly. Filter with category to cut the volume. Needs a company number.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| category | No | Restrict to one category, e.g. accounts, confirmation-statement, officers, mortgage, address, capital, incorporation, resolution, insolvency. | |
| start_index | No | Zero-based offset into the full result set. Use pagination.has_more to decide. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. | |
| items_per_page | No | How many records to return. Defaults to the API default; the maximum is 100. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| filings | Yes | |
| pagination | Yes | Where this page sits in the full result set. |
| company_number | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds genuine behavioral context beyond the read-only annotations by explaining that filing descriptions come back as un-translated Companies House template keys and why partial translation was avoided. It also hints at response volume by recommending category filtering, which is useful for an agent deciding how to call the tool.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is compact and front-loaded: it states the core purpose first, then use cases, then an important output-format caveat, then a filtering tip. Every sentence earns its place without verbose framing or redundant schema repetition.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the output schema and fully described input parameters, the description covers the important operational details: what filings are included, how keys are represented, why translation is skipped, and how to reduce volume. It could be slightly stronger by mentioning pagination behavior explicitly, but the start_index parameter and output schema already carry that burden.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the parameters are fully documented in the schema. The description adds only minimal parameter-related guidance, such as using category to cut volume and requiring a company number, which mostly restates what the schema already says.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description opens with a specific statement of what the tool returns — "What a company has filed and when" — and lists concrete filing types such as accounts, confirmation statements, and officer changes. This clearly distinguishes it from sibling tools like get_company or get_officers by focusing on filing history events.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives explicit use cases: judging whether a company files on time, seeing when accounts were last made up, and watching a competitor's filing cadence. It also notes the need for a company number and suggests filtering with category, though it does not explicitly name alternative tools or state when not to use it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_insolvencyGet insolvency historyARead-onlyIdempotent
Insolvency cases registered against a company: the type of proceeding, its key dates, and the insolvency practitioners appointed. Call it when get_company reports has_insolvency_history, or as part of a credit or supplier risk check. A company with no insolvency history returns a not-found error rather than an empty list, which is a quirk of the API and means exactly what it sounds like. Needs a company number.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| cases | Yes | |
| case_count | Yes | |
| company_number | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Beyond readOnly/idempotent annotations, it discloses a genuinely surprising API quirk: no history yields a not-found error rather than an empty list. This prevents an agent from misinterpreting an error as a failure of the tool itself.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three tight sentences: what the tool returns, when to use it, and the one edge case an agent must know. Every sentence earns its place and important constraints are front-loaded.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
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 need not re-specify return fields. It covers purpose, trigger, error behavior, and required input, and annotations cover safety, making this complete for reliable invocation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so both company_number and verbose are already documented in the schema. The description adds only a high-level 'Needs a company number' restatement, so the baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names a specific resource (insolvency cases registered against a company) and the meaningful output (proceeding type, key dates, practitioners). It also ties it to get_company's has_insolvency_history flag, which differentiates it from sibling tools without needing to inspect schemas.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives explicit trigger conditions: call it when get_company reports has_insolvency_history or as part of a credit/supplier risk check. It does not enumerate exclusions or alternatives, but there is no dedicated sibling insolvency tool, and 'Needs a company number' clarifies a prerequisite.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_officer_appointmentsGet an officer’s appointmentsARead-onlyIdempotent
Every company an officer is or has been appointed to. This is the conflict-of-interest and director-network tool: run it across a board to find the shared directorship nobody declared, or across one person to see whether they have a history of dissolved companies. Needs an officer_id, which comes from get_officers or find_officer and never from a name.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| officer_id | Yes | Officer identifier from get_officers or find_officer, not a person’s name. | |
| start_index | No | Zero-based offset into the full result set. Use pagination.has_more to decide. | |
| items_per_page | No | How many records to return. Defaults to the API default; the maximum is 100. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| name | No | |
| officer_id | Yes | |
| pagination | Yes | Where this page sits in the full result set. |
| appointments | Yes | |
| date_of_birth | No | |
| active_appointment_count | Yes | Derived from the returned page, not the whole set. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly/idempotent/non-destructive, and the description adds behavior beyond that: the result includes both current and historical appointments ('is or has been appointed to') and is suited for spotting dissolved-company history. No annotation contradiction exists.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three tightly written sentences: core function, illustrative use cases, and the key input requirement. Every sentence contributes new information and the most important facts are front-loaded.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only list endpoint with a full output schema and fully documented parameters, the description covers the essential context: what data is returned, why an agent would use it, and where the required identifier comes from. Nothing critical is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema carries most parameter documentation. The description adds important semantic value for officer_id by stating it must come from get_officers or find_officer and not from a name, which prevents a common misuse.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states the exact resource ('Every company an officer is or has been appointed to') and positions the tool as the conflict-of-interest/director-network lookup. This clearly distinguishes it from siblings like get_company or get_officers, which have different scopes.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives concrete when-to-use scenarios: running across a board to expose undeclared shared directorships, or checking a person's history of dissolved companies. It does not explicitly list sibling alternatives or exclusion conditions, but the use-case framing is clear enough to route an agent correctly.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_officersGet company officersARead-onlyIdempotent
The directors, secretaries and members of one company, current and resigned, each with an officer_id you can pass to get_officer_appointments. Use it to see who runs a company, or as the first step in a conflict-of-interest check across a board. Service addresses are withheld unless verbose is set, because they are personal data and are rarely what the question needs. Needs a company number; call find_company first if you only have a name.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| start_index | No | Zero-based offset into the full result set. Use pagination.has_more to decide. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. | |
| items_per_page | No | How many records to return. Defaults to the API default; the maximum is 100. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| officers | Yes | |
| pagination | Yes | Where this page sits in the full result set. |
| active_count | No | |
| company_number | Yes | |
| inactive_count | No | Appointments that ended because the company did, rather than by resignation. Non-zero on a dissolved company, and the reason active + resigned can fall short of the total. |
| resigned_count | No |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the tool read-only and idempotent, and the description adds non-obvious behavior: service addresses are withheld for privacy unless verbose is set. It also discloses that verbose returns a much larger raw payload, which helps the agent set expectations beyond what the annotations convey.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Four sentences, each earning its place: the tool's output, the use cases, the privacy caveat, and the prerequisite. The most actionable information is front-loaded, and there is no redundant wording.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
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 does not need to explain return values. Combined with full schema documentation for all parameters, the description covers purpose, usage context, privacy behavior, and how to chain with sibling tools, so nothing critical is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, which sets a baseline of 3. The description adds extra meaning for company_number by emphasizing it cannot be a name and requires find_company first, and for verbose by explaining the privacy trade-off. The remaining parameters are adequately documented in the schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource: get officers of one company, including current and resigned. It also distinguishes itself from related siblings by noting each result carries an officer_id to pass to get_officer_appointments, making it clearly different from find_officer or get_officer_appointments.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Explicitly gives when to use the tool: to see who runs a company or as the first step in a conflict-of-interest check. It also names the prerequisite (company number) and directs the agent to call find_company first if only a name is available.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
get_pscGet persons with significant controlARead-onlyIdempotent
Who OWNS a company. Use this for any question about ownership, shareholders, beneficial owners or who is ultimately behind a business — the company profile does not carry ownership and get_company will not answer it. Returns each person or entity with significant control: how much they own (shareholding band), how that control is held (voting rights, right to appoint directors), and whether the interest is current or ceased. Ownership is often not the same as the directors, so this is a different question from get_officers. Where a company cannot identify a controller it files a statement instead of a person, and that statement is returned in the name field. Needs a company number.
| Name | Required | Description | Default |
|---|---|---|---|
| verbose | No | Also return the untouched Companies House payload under `raw`, alongside the shaped result. Roughly two and a half times the size; use it only when a field you need is missing from the shaped result. | |
| start_index | No | Zero-based offset into the full result set. Use pagination.has_more to decide. | |
| company_number | Yes | Eight-character Companies House number, such as 00000006 or SC123456. Leading zeros may be omitted. This tool does not accept a company name — call find_company first if that is all you have. | |
| items_per_page | No | How many records to return. Defaults to the API default; the maximum is 100. |
Output Schema
| Name | Required | Description |
|---|---|---|
| raw | No | The untouched Companies House payload. Present only when verbose was true. |
| meta | Yes | Provenance and budget for this answer. |
| pagination | Yes | Where this page sits in the full result set. |
| controllers | Yes | |
| active_count | No | |
| ceased_count | No | |
| company_number | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds meaningful behavior beyond the annotations: it explains the returned fields, states that interests can be current or ceased, and discloses the edge case where a statement is returned in the name field instead of a person. This provides actionable behavioral context without contradicting 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.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is dense but every sentence earns its place: it states the core purpose, gives usage context, distinguishes from siblings, explains the return data, and covers a key edge case. The most important routing signal is front-loaded with 'Who OWNS a company,' and the final 'Needs a company number' is a useful practical requirement. There is no filler or repetition.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only, idempotent tool with an output schema and 100% schema parameter coverage, the description is complete. It explains what the tool returns, when to use it, how it differs from related tools, how to handle the statement fallback, and the prerequisite of a company number. Pagination is already covered by the schema's start_index and items_per_page descriptions, so no further behavioral detail is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the input schema already documents all four parameters thoroughly, including company_number format, verbose behavior, pagination offset, and items_per_page. The description adds only 'Needs a company number' and the hint to call find_company if only a name is available, which the schema already states. This is the baseline 3 case: the schema carries the parameter-semantics burden and the description does not need to compensate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description opens with the concrete, memorable phrase 'Who OWNS a company' and immediately identifies the resource: persons with significant control, including shareholding bands and control mechanisms. It also differentiates itself from related tools by explicitly stating that get_company will not answer ownership questions and that ownership is a different question from get_officers, so an agent can distinguish it from siblings without opening schemas.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives explicit when-to-use guidance: 'Use this for any question about ownership, shareholders, beneficial owners or who is ultimately behind a business.' It also names exclusions and alternatives, warning that get_company will not answer this and directing users to find_company if they only have a company name. This is exactly the kind of routing context an agent needs.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
screen_companiesScreen a list of companiesARead-onlyIdempotent
Use this whenever the question is about MORE THAN ONE company — a list, a comparison, "which of these", a batch from procurement, anything with several names or numbers in it. Prefer it over calling company_snapshot repeatedly: it costs a quarter of the requests and returns a table you can read at a glance. Screens up to 50 companies and returns one row each: status, age, and which signals were found. Names that match more than one company are never guessed at; they come back under unresolved with their candidates so you can ask which was meant. Anything skipped for want of rate-limit budget comes back under not_screened with the reason, so the table is never quietly shorter than the list you passed in. Rows carry signal codes only — call company_snapshot on one company number for the detail behind them. Officers are excluded by default because they cost an extra request per company; sections_used says what the signals could see.
| Name | Required | Description | Default |
|---|---|---|---|
| companies | Yes | Company names or numbers. Mixed input is fine. Maximum 50 per call. | |
| include_charges | No | Include charges. On by default. | |
| include_officers | No | Fetch officers too, enabling the no_active_officers and recent_officer_departures signals. Off by default: it adds one request per company. | |
| include_insolvency | No | Include insolvency cases. On by default. |
Output Schema
| Name | Required | Description |
|---|---|---|
| meta | Yes | Provenance and budget for this answer. |
| screened | Yes | |
| requested | Yes | |
| unresolved | Yes | Inputs that could not be resolved to exactly one company. Never guessed at. |
| not_screened | Yes | Inputs deliberately skipped, with the reason. Nothing is dropped silently. |
| sections_used | Yes | Signals in this table can only reflect these sections. Officers are off by default. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark this read-only/idempotent, but the description adds substantial behavioral context: one row per company, signal codes only, unresolved names returned with candidates rather than guessed, not_screened entries with reasons for rate-limit skips, and officer handling with cost implications. None of this is visible in 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.
Is the description appropriately sized, front-loaded, and free of redundancy?
Dense but every sentence contributes: usage guidance is front-loaded, the alternative is named early, and edge-case behaviors are explained in logical order. No filler or repetition of schema content.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's complexity and the presence of an output schema, the description covers all necessary operational details: limits, return shape, unresolved/not_screened behavior, signal-code usage, and officer cost trade-offs. Nothing an agent needs to safely invoke it is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so the baseline is 3, but the description adds meaningful context beyond the schema: it explains that names matching multiple companies are not guessed, unresolved results include candidates, and include_officers carries an extra request cost. This helps an agent choose parameters more wisely.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Description states a specific verb and resource ('Screen a list of companies') and immediately clarifies it is for MORE THAN ONE company. It explicitly contrasts with company_snapshot, so an agent can distinguish the intended use without inspecting schemas.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Provides explicit when-to-use conditions: lists, comparisons, batches, and anything with several names or numbers. It also names the alternatives (company_snapshot for detail, repeated calls as the less efficient option) and explains when to switch.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
11 tool updates
v0.4.0- Changed
company_snapshot7 fields changed- changed
Output schema / properties / charges / properties / holders / descriptionPrevious value: -"Who holds the outstanding charges."New value: +"Holders of returned charges not recorded as fully satisfied." - added
Output schema / properties / charges / properties / part_satisfied_countAdded value: +{ + "type": "number" +} - changed
Output schema / properties / charges / requiredPrevious value: -[ - "total_count", - "outstanding_count", - "satisfied_count", - "holders" -]New value: +[ + "total_count", + "outstanding_count", + "satisfied_count", + "part_satisfied_count", + "holders" +] - changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply." - added
Output schema / properties / officers / properties / paginationAdded value: +{ + "additionalProperties": false, + "description": "Coverage of the fetched officer page, before filtering to active officers. Follow get_officers pagination for the full list; counts describe the whole register.", + "properties": { + "has_more": { + "description": "More records exist. Call again with start_index advanced by `returned`.", + "type": "boolean" + }, + "items_per_page": { + "type": "number" + }, + "returned": { + "description": "How many records are in this response.", + "type": "number" + }, + "start_index": { + "type": "number" + }, + "total_results": { + "type": "number" + } + }, + "required": [ + "start_index", + "items_per_page", + "total_results", + "returned", + "has_more" + ], + "type": "object" +} - changed
Output schema / properties / officers / requiredPrevious value: -[ - "active" -]New value: +[ + "pagination", + "active" +] - changed
Output schema / properties / signals / items / properties / code / enumPrevious value: -[ - "dissolved", - "insolvency_proceedings", - "not_active", - "insolvency_history", - "accounts_overdue", - "confirmation_statement_overdue", - "outstanding_charges", - "floating_charge_over_all_assets", - "no_active_officers", - "recent_officer_departures", - "incorporated_within_last_year", - "registered_office_in_dispute" -]New value: +[ + "dissolved", + "insolvency_proceedings", + "not_active", + "insolvency_history", + "accounts_overdue", + "confirmation_statement_overdue", + "outstanding_charges", + "part_satisfied_charges", + "floating_charge_over_all_assets", + "no_active_officers", + "recent_officer_departures", + "incorporated_within_last_year", + "registered_office_in_dispute" +]
- Changed
find_company2 fields changed- added
Input schema / properties / query / maxLengthAdded value: +256 - changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
find_officer2 fields changed- added
Input schema / properties / query / maxLengthAdded value: +256 - changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_charges1 field changed- changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_company1 field changed- changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_filing_history1 field changed- changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_insolvency1 field changed- changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_officer_appointments1 field changed- changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_officers2 fields changed- added
Output schema / properties / inactive_countAdded value: +{ + "description": "Appointments that ended because the company did, rather than by resignation. Non-zero on a dissolved company, and the reason active + resigned can fall short of the total.", + "type": "number" +} - changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
get_psc1 field changed- changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply."
- Changed
screen_companies8 fields changed- added
Input schema / properties / companies / items / maxLengthAdded value: +256 - changed
Output schema / properties / meta / properties / licence / descriptionPrevious value: -"Companies House data is Open Government Licence v3.0."New value: +"OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply." - added
Output schema / properties / screened / items / properties / metaAdded value: +{ + "additionalProperties": false, + "description": "Provenance and budget for this answer.", + "properties": { + "age_seconds": { + "description": "How long ago the cached answer was retrieved. Absent for a live answer.", + "type": "number" + }, + "cached": { + "description": "Answer came from the local cache rather than a live request.", + "type": "boolean" + }, + "licence": { + "const": "OGL-v3.0", + "description": "OGL v3.0 applies to eligible public-sector information. Personal data and other OGL exclusions are not licensed by this label; applicable data-protection duties still apply.", + "type": "string" + }, + "rate_limit_remaining": { + "description": "Requests still available in the current five-minute window. Pace long runs by this.", + "type": "number" + }, + "rate_limit_resets_in_ms": { + "description": "Milliseconds until more budget becomes available.", + "type": "number" + }, + "stale": { + "description": "Answer came from an expired cache entry because Companies House was unreachable. Treat the data as possibly out of date.", + "type": "boolean" + } + }, + "required": [ + "cached", + "stale", + "rate_limit_remaining", + "rate_limit_resets_in_ms", + "licence" + ], + "type": "object" +} - added
Output schema / properties / screened / items / properties / officers_paginationAdded value: +{ + "additionalProperties": false, + "description": "Officer page coverage when officers were requested.", + "properties": { + "has_more": { + "description": "More records exist. Call again with start_index advanced by `returned`.", + "type": "boolean" + }, + "items_per_page": { + "type": "number" + }, + "returned": { + "description": "How many records are in this response.", + "type": "number" + }, + "start_index": { + "type": "number" + }, + "total_results": { + "type": "number" + } + }, + "required": [ + "start_index", + "items_per_page", + "total_results", + "returned", + "has_more" + ], + "type": "object" +} - added
Output schema / properties / screened / items / properties / sections_includedAdded value: +{ + "description": "Sections actually fetched for this company.", + "items": { + "type": "string" + }, + "type": "array" +} - added
Output schema / properties / screened / items / properties / sections_unavailableAdded value: +{ + "items": { + "additionalProperties": false, + "properties": { + "code": { + "description": "The error code from the failed request.", + "type": "string" + }, + "message": { + "type": "string" + }, + "section": { + "description": "Which part of the snapshot could not be read.", + "type": "string" + } + }, + "required": [ + "section", + "code", + "message" + ], + "type": "object" + }, + "type": "array" +} - changed
Output schema / properties / screened / items / properties / signal_codes / items / enumPrevious value: -[ - "dissolved", - "insolvency_proceedings", - "not_active", - "insolvency_history", - "accounts_overdue", - "confirmation_statement_overdue", - "outstanding_charges", - "floating_charge_over_all_assets", - "no_active_officers", - "recent_officer_departures", - "incorporated_within_last_year", - "registered_office_in_dispute" -]New value: +[ + "dissolved", + "insolvency_proceedings", + "not_active", + "insolvency_history", + "accounts_overdue", + "confirmation_statement_overdue", + "outstanding_charges", + "part_satisfied_charges", + "floating_charge_over_all_assets", + "no_active_officers", + "recent_officer_departures", + "incorporated_within_last_year", + "registered_office_in_dispute" +] - changed
Output schema / properties / screened / items / requiredPrevious value: -[ - "input", - "company_number", - "name", - "signal_codes", - "signal_count" -]New value: +[ + "input", + "company_number", + "name", + "signal_codes", + "signal_count", + "sections_included", + "sections_unavailable", + "meta" +]
11 tool updates
v0.2.0- First observed
company_snapshot - First observed
find_company - First observed
find_officer - First observed
get_charges - First observed
get_company - First observed
get_filing_history - First observed
get_insolvency - First observed
get_officer_appointments - First observed
get_officers - First observed
get_psc - First observed
screen_companies
TDQS
Scored across 11 tools
Each tool targets a distinct resource/action: company search vs company profile, officer search vs officer list vs officer appointments, and individual getters vs aggregate snapshot/batch screening. The one area of potential overlap, company_snapshot with get_company/get_officers/get_charges/get_insolvency, is explicitly described as a replacement for combined calls, so agents can choose correctly.
The naming mostly follows a clear find_/get_ pattern, where find_ is for search and get_ is for retrieval by an ID. The pattern is weakened slightly by company_snapshot and screen_companies, which are descriptive but break the verb-prefix convention.
11 tools is well within the ideal range and every tool earns its place: seven single-resource lookups, two search entry points, one aggregate snapshot, and one batch screening tool. The count feels deliberately scoped for a Companies House screening domain rather than padded or thin.
The surface covers the full screening workflow: company identification, company status, officers, ownership/PSC, charges, insolvency, filing history, officer appointment networks, individual deep-dives, and batch comparison. There are no obvious dead ends or missing operations that would prevent an agent from answering typical due-diligence questions.
Maintenance
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