Getting Started

The Neos Partner API is a REST API for connecting Neos, a legal case management platform for law firms, to other systems. Through the API you can create and manage cases, intakes, contacts, documents, calendar events, webhooks, and more, enabling workflows like intake capture, document sync, and bi-directional data exchange with external systems.

These docs are for anyone building on the API: a firm connecting its own systems, a developer the firm hires, or a vendor whose product the firm uses. Access is granted through a request and approval process managed by Assembly Software.

API Access & Use Policy

API access is included for every Neos customer, up to the service protection limit that comes with the firm's subscription (see Request Limits).

The API is for connecting Neos to the systems a firm uses to run its practice. All use of the Neos API is subject to Assembly Software's General Terms and Conditions and the API Agreement you accept during onboarding.

Permitted

Business systems and service vendors the firm uses: accounting, e-signature, phone and texting, payments, records retrieval, lien resolution, intake, and CRM tools.
AI assistants such as Claude, ChatGPT, or Gemini, connected to the firm's own Neos data.
The firm's own infrastructure, such as a data warehouse or reporting tools.
Custom tools a firm builds, or hires a developer to build, for its own use.

Not Permitted

Sharing API credentials with a competing vendor, or letting a vendor build its product on a firm's access without Assembly Software's knowledge and approval.
Browser bots, screen scraping, or other automation that runs through the Neos interface instead of the API.
Reselling access or using Neos to provide services to other firms.

Vendors Building Products for Many Firms

If you are a vendor building a product that connects to Neos for many firms, you will work with Assembly Software through the Integration Partnership Program, not through an individual firm's API access. Partner usage terms, limits, and pricing are set in each partner agreement. Start with the same Integration Request and Assembly Software will route you to the program.

If a vendor asks your firm for Neos API credentials so it can build or run its product, send the vendor to your Assembly account team.

Onboarding Steps

Create an Account — Register in the Neos Developer Portal. You will be asked to agree to our API Agreement during signup.
Submit an Integration Request — Tell us what you want to connect, which firm or firms it is for, and your integration requirements.
We Review It — Assembly Software confirms the integration fits the API Access & Use Policy. If it is a better fit for the Integration Partnership Program, we will point you there.
Sign the API Agreement — Required before staging access is granted.
Subscribe to an API — Once approved, subscribe to an API product to receive your Subscription Key and access the documentation.

Integration Phases

Phase	Description
Discovery	Initial conversation to align on integration goals and requirements.
Approval	Assembly Software reviews the request against the API Access & Use Policy and approves it, or routes it to the Integration Partnership Program.
Development	Access to a shared staging environment for building and testing.
Go-Live	Production credentials issued once a firm admin contact is on file for the firm.

Key Standards

Before you start building, be aware of the following non-negotiable requirements:

Test only in the staging environment — never in production.
Use the API, never browser automation or screen scraping of the Neos interface.
Implement duplicate checks before creating cases, intakes, or contacts.
Use POST /v1/advancedsearch/search/results for searching — do not use GET-based search for bulk queries.
Cache the data you work with and sync only what changed since your last pull. Use webhooks rather than frequent polling.
Reuse your access token for its four-hour lifetime rather than logging in on every call.
Use PATCH for partial updates. Only use PUT when replacing a full object, and always retrieve the current state first.
Implement retry logic with exponential backoff and log all failures.
Protect data with encryption in transit and at rest, and use role-based access controls.

What's Next

Authentication — How to create an integration user, activate your integration, and obtain a Bearer Token.
Neos API Guidelines & Best Practices — Credential details, request limits, and integration standards.
Frequently Asked Questions — Common error codes and troubleshooting.

Support

Submit a Neos Integration Support Request with request samples, API details, error logs, and steps to reproduce.