Ideal Postcodes for AI agents

Ideal Postcodes provides UK and international address search, postcode lookup, and address validation, used by developers to catch bad addresses and speed up checkout and signup forms. Connect it once through Arc0, and your agent, or Claude, ChatGPT and Cursor, can use it through one MCP endpoint, limited to what each user approved.

Connect Ideal Postcodes See the 9 actions ↓

Developer toolsAPI keyMCP + RESTideal-postcodes.co.uk

AUDIT LOG · IDEAL POSTCODESPOLICY: acme-support

09:41:07 · claude · u_8f2read

ideal_postcodes.search_addresses

Search Addresses✓ allowed · 212ms

09:41:08 · claude · u_8f2read

ideal_postcodes.resolve_place

Resolve Place✓ allowed · 164ms

EVERY IDEAL POSTCODES CALL, ON THE RECORD

01 · USE CASES

What agents do in Ideal Postcodes.

Look up an address by postcode

Look up the full address list for a UK postcode entered at checkout.

Validate a customer address

Validate a submitted address to catch formatting errors before an order ships.

Autocomplete an address search

Suggest matching addresses as a customer types a partial address into a form.

02 · ACTIONS

9 Ideal Postcodes actions, graded by risk.

Every Ideal Postcodes action is tagged read, write or destructive, so one policy covers the whole app and new actions inherit the right default.

read

Look things up. Allowed by default.

ideal_postcodes.search_addresses
Search Addresses
ideal_postcodes.find_place_suggestions
Find Place Suggestions
ideal_postcodes.find_address_suggestions
Find Address Suggestions
ideal_postcodes.get_address_by_identifier
Get Address by Identifier
ideal_postcodes.resolve_place
Resolve Place
ideal_postcodes.lookup_postcode
Lookup Postcode
ideal_postcodes.validate_address
Validate Address
ideal_postcodes.validate_contact
Validate Contact
ideal_postcodes.resolve_address_suggestion
Resolve Address Suggestion

write

Create and change things. Allow, or ask the user first.

No write actions.

destructive

Delete, cancel or archive. Ask first, or deny outright.

No destructive actions.

03 · HOW IT WORKS

Ideal Postcodes in three steps.

01Your users connect Ideal PostcodesThey add their Ideal Postcodes api key on Arc0 Connect, under your brand. It goes straight into the vault.
02You set the rulesReads run, and writes like “updates” can wait for the user to approve.
03Any agent can actYour agent calls Ideal Postcodes through the Arc0 SDK or MCP, and so can Claude, ChatGPT and Cursor. Every call lands on the audit log.

POLICY.TS

await arc0.policies.set('ideal_postcodes', {
  read: 'allow',
  write: 'ask',        
  destructive: 'deny',  
})

# Claude Code: the same connection, one URL
$ claude mcp add --transport http arc0 \
    https://mcp.arc0.ai/u/u_8f2

04 · AUTH AND DATA

How Ideal Postcodes connects.

Users add their Ideal Postcodes api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.

The same Ideal Postcodes connection serves your agent over MCP and your own backend over REST and the proxy, so a user connects once. How Arc0 handles credentials →

AUTH: API key
CREDENTIALS: Per-tenant encrypted vault
MODEL SEES: Results only, never credentials
AUDIT LOG: Every call, on every plan

05 · WORKS WITH

Use Ideal Postcodes from any agent.

Claude

ChatGPT

Cursor

Codex

VS Code

OpenAI Agents SDK

Claude Agent SDK

Vercel AI SDK

Mastra

LangGraph

06 · RELATED

More developer tools apps.

Addressfinder17 actions

Addresszen2 actions

Alchemy36 actions

ALL DEVELOPER TOOLS APPS →

07 · FAQ

Ideal Postcodes and Arc0, answered.

Q01

Can I use Ideal Postcodes with Claude, ChatGPT or Cursor?

Yes. Connect Ideal Postcodes to Arc0 once, then add your Arc0 MCP URL to Claude, ChatGPT, Cursor, Claude Code or any other remote-MCP client. Each assistant only gets the Ideal Postcodes actions you allow.

Q02

How do users connect Ideal Postcodes?

Users add their Ideal Postcodes api key on Arc0 Connect. It is encrypted in the vault, never shown to the model, and each user can rotate or revoke it at any time.

Q03

Which Ideal Postcodes actions can my agent take?

9 in total: 9 read, 0 write and 0 destructive. Your policies decide which of them each agent may call.

Q04

Can I make my agent read-only in Ideal Postcodes?

Yes. Allow read actions and deny writes in the Ideal Postcodes policy. Your agent can still look things up, and any write it attempts is blocked and logged.

Q05

Can my own backend call Ideal Postcodes too?

Yes. The same Ideal Postcodes connection is available over REST and through the Arc0 proxy, so your product and your agent share one connection per user.

Get started

Plug Ideal Postcodes into your agent.

Your users connect Ideal Postcodes once, under your brand. Your agent gets 9 actions behind your policies, with every call on the record.

Connect Ideal Postcodes Browse all apps →

Free to build · MCP + REST · Audit log on every plan