# Alto (Vebra / Zoopla)

**Canonical:** https://apis.io/providers/alto-vebra/  
**Website:** https://www.altosoftware.co.uk/  
**APIs profiled:** 4

Alto — formerly Vebra Alto, and still trading through vebra.com — is the United Kingdom's most widely deployed estate agency CRM, used by more than 6,000 sales and lettings agency branches to run valuations, listings, applicant matching, offers, sales and lettings progression, tenancies, property management, work orders and client accounting. It is owned by Houseful Limited, the parent of the Zoopla portal, which places Alto at the exact chokepoint of the UK residential market — the country has no MLS, so listings reach Rightmove and Zoopla through agency CRM software rather than a shared cooperative database, and Alto is the largest of those pipes. Its API posture is genuinely strong on the contract side and closed on the access side: Alto publishes an open, unauthenticated developer portal at developers.vebraalto.com carrying a complete OpenAPI 3.0.4 document (95 paths, 112 operations across 27 resource families) served verbatim from api-docs.vebraalto.com, alongside 26 documented CloudEvents 1.0 webhook event types and 101 published OAuth scope strings. But credentials are partner-only — a developer must register an integration in Alto Connect, be bound by an existing contract with Vebra Solutions, and then wait for an individual agency to activate the integration and issue an AgencyRef before a single call can be made. Sibling Zoopla portal product APIs (Leads, Premium Listing Activations, Weekly Featured Property) are documented publicly at developers.zoopla.co.uk with downloadable specs but are likewise restricted to contracted Zoopla agency customers. There is no SDK, CLI, Postman collection, MCP server or status page anywhere in the estate, and no RESO Web API or Data Dictionary certification exists — RESO is a North American NAR-driven standard with no UK counterpart. Alto publishes no open data; the UK's open property layer sits with HM Land Registry and Ordnance Survey, not with the private CRM duopoly feeders.

## Kin Score — 50.5 / 100 (developing)

Scored 2026-08-21 under rubric 0.12.0. Trend: flat (+0.0 from 50.5).

| Facet | Score |
|---|---|
| Discoverability | 92.6 |
| Contract Quality | 57.5 |
| Governance | 16.7 |
| Contract Governance | 16.7 |
| Operational Transparency | 36.8 |
| Developer Ergonomics | 66.1 |
| Commercial Clarity | 34.2 |
| Access Clarity | 34.2 |

## Agent readiness — 42.9 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | documented |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | no |
| Error Semantics | verified |
| OpenAPI Examples | partial |
| Rate Limit Signal | no |
| Event Surface Described | derived |
| Agent Skills | derived |
| Well Known Catalog | no |
| Consent Identity | yes |
| Agent Card | no |
| Dry Run Mode | no |

## APIs (4)

- **Alto API** — The full Alto REST API for UK estate agency operations — 95 documented paths across 27 resource families covering contacts and applicants, property inventory, listings and media...
- **Zoopla Leads API** — Swagger 2.0 poll API for retrieving applicant leads and appraisal (valuation) leads generated on the Zoopla portal, published by Houseful for contracted Zoopla agency customers ...
- **Zoopla Premium Listing Activations API** — OpenAPI 3.0.0 contract for activating and inspecting Zoopla Premium Listing products against a property listing, exposed at /products/premium-listings and /products/premium-list...
- **Zoopla Weekly Featured Property (WFP) Activations API** — OpenAPI 3.0.0 contract for activating Zoopla Weekly Featured Property placements against a listing, exposed at /products/weekly-featured-properties and /products/weekly-featured...

## MCP servers (1)

- **Candidate MCP tool surface derived from the OpenAPIs**

## Agentic access (1)

- **Alto Vebra Agentic Access** — 121 operations · 48 acting

## Security (3)

- **Alto Vebra Authentication** — apiKey/oauth2 · 5 schemes
- **Alto Vebra Domain Security** — TLSv1.2 · HSTS · DMARC
- **Alto Vebra Vulnerability Disclosure** — Hackerone · security.txt · contact published

## Tags

Real-Estate, United Kingdom, PropTech, Property Listings, CRM, Property Management, Rentals, Conveyancing, Estate Agency, Tenancy, Webhook, Event, Lettings, Sales Progression, Property Data, Real Estate Software

---

Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/alto-vebra/). Scores are computed from the provider's own public artifacts under a published rubric.