Brex

Brex is the first fully unified spend platform with global corporate cards, expense management, reimbursements, travel, and bill pay. Brex makes it easy for finance teams to control all of their spend, all in one place. Using the Brex API, you can power your internal tools and create custom workflows.

Brex publishes 11 API contracts indexed on the APIs.io network, including Budget Programs API, Budgets API, Spend Limits API, and 8 more. Tagged areas include Bill Pay, Corporate Cards, Expenses, Reimbursement, and Spending.

The Brex catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

Brex’s developer surface includes authentication and 9 more developer resources.

📡 Profile data on GitHub

22.7/100 emerging ▬ flat Agent 53/100 agent ready Heartbeat 78/100 alive Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemiumSelf serve⚡ Free to try

1 published contract 1 MCP Servers

Bill Pay Corporate Cards Expenses Reimbursement Spending Accounting Expense Management

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Financial Planning & Analysis

BC-230

Budgets

POST /v1/budgets POST /v1/budgets/{id}/archive POST /v2/budgets

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 22.7/100 · emerging

Contract Quality 8.5 / 19

Developer Ergonomics 1.8 / 15

Access Clarity 1.2 / 15

Operational Transparency 1.0 / 10

Contract Governance 1.0 / 9

Discoverability 5.0 / 8

Regulatory Posture 1.6 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 53/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 6 / 6

Protected Resource Metadata 5 / 5

Registration Without a Human 6 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Payments regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

Show this score on your site.

It updates itself when the score changes. Paste this where you link to your API docs:

<a href="https://apis.io/providers/brex/"><img src="https://apis.io/badge/brex/card.svg" alt="Brex on APIs.io — Kin Score by API Evangelist"></a>

Other styles, a README pill and a shields.io endpoint are on the badge page.

Raise your score.

Agent readiness — checks not met, largest first (exact, from this profile):

Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too
Agent Skills +5 pts — skills artifact present, graded by who authored it
Agentic Commerce Well-Known Document +5 pts — a parsing /.well-known/ucp.json or acp.json declaring a version and at least one service, OR (0.27) a live x402 payment challenge from _data/x402-adoption.json — `self` when its endpoints are on the provider's own domain, `platform` when they are on a vendor's

3 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Access Clarity scores 7.9 — up to +18.4 composite points
Developer Ergonomics scores 11.9 — up to +17.6 composite points
Contract Quality scores 45.3 — up to +13.7 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/brex/apis.yml: open an issue on github.com/api-evangelist/brex to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Accounting and Finance Ops	undeclared	-	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

Standards implemented 4

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

Model Context Protocol (MCP)

measured — observed by APIs.io (verified)

OAuth 2.0 Protected Resource Metadata

measured — observed by APIs.io (verified)

Dynamic Client Registration

measured — observed by APIs.io (published)

OpenAPI

measured — observed by APIs.io (published)

APIs 11

Individual APIs this provider publishes, each with its own machine-readable definition.

Brex Budget Programs API

The Budget Programs API from Brex — 2 operation(s) for budget programs.

Brex Budgets API

The Budgets API from Brex — 6 operation(s) for budgets.

Brex Spend Limits API

The Spend Limits API from Brex — 3 operation(s) for spend limits.

Brex Cards API

Endpoints for card management.

Brex Companies API

The Companies API from Brex — 1 operation(s) for companies.

Brex Cost Centers API

Endpoints for cost center management.

Brex Departments API

Endpoints for department management.

Brex Legal Entities API

Endpoints for legal entities.

Brex Locations API

Endpoints for location management.

Brex Titles API

Endpoints for title management.

Brex Users API

Endpoints for user management.

Scroll for all 11

Open Collections 4

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Brex Budgets Budget Programs API

OPEN COLLECTION

Brex Budget Programs Budgets API

OPEN COLLECTION

Brex Budgets Budget Programs Spend Limits API

OPEN COLLECTION

Brex Budgets API

OPEN COLLECTION

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

Brex MCP Server

Remote MCP server at api.brex.com over HTTP.

MCP SERVER

Brex API pricing

Not yet checked against Brex's own pricing page. Compiled by API Evangelist on 2026-05-04; confirm before you rely on a figure. A free plan or tier is listed.

Plan	Price
Free freemium	Free
Professional paid	Free
Enterprise enterprise	—

Plan details, limits and sources →

Rate limits

Free Tier Default: 10 requests per minute
Free Tier Monthly Quota: 1000 requests per month
Professional Tier Default: 100 requests per minute

Compiled by API Evangelist, not yet checked against Brex's documentation. All 5 limits →

Pricing Plans 1

Published pricing tiers and plan structures.

Brex Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Brex Rate Limits

5 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

Brex

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Brex Finops

FINOPS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Brex Webhooks API

AsyncAPI 2.6 description of the Brex Webhooks surface. Brex uses webhooks to deliver real-time notifications when events happen in the accounts that you manage. Subscribers regi...

ASYNCAPI

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Brex — asyncapi rules

8 rules · 1 errors 7 warnings

SPECTRAL

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Brex Authentication

http · 1 scheme

SECURITY

Brex Domain Security

TLSv1.3 · DMARC

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Brex Agentic Access

17 operations · 9 acting

AGENTIC

Resources

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LlmsText

LlmsText

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 1

Status, limits, changes, and where to get help

RateLimits

RateLimits

Commercial 2

Pricing, plans, and the legal terms of use

Plans

Plans

FinOps

FinOps

Company 1

The organization behind the API

LinkedIn

Other 1

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Source (apis.yml)

aid: brex
url: https://raw.githubusercontent.com/api-search/brex/refs/heads/main/apis.yml
common:
- type: Plans
  url: plans/brex-plans-pricing.yml
- type: RateLimits
  url: rate-limits/brex-rate-limits.yml
- type: FinOps
  url: finops/brex-finops.yml
- type: CapabilityMap
  url: capabilities/brex-capability-edges.yml
  name: Brex Business Capability Map
- type: AgenticAccess
  url: agentic-access/brex-agentic-access.yml
- type: DomainSecurity
  url: security/brex-domain-security.yml
- type: Authentication
  url: authentication/brex-authentication.yml
- type: GitHubOrganization
  url: https://github.com/brexhq
- type: LinkedIn
  url: https://www.linkedin.com/company/brexhq
- type: LlmsText
  url: https://developer.brex.com/llms.txt
apis:
- aid: brex:brex-budget-programs-api
  name: Brex Budget Programs API
  description: The Budget Programs API from Brex — 2 operation(s) for budget programs.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Budget Programs
  properties:
  - type: OpenAPI
    url: openapi/brex-budget-programs-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/brex-webhooks-asyncapi.yml
- aid: brex:brex-budgets-api
  name: Brex Budgets API
  description: The Budgets API from Brex — 6 operation(s) for budgets.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Budgets
  properties:
  - type: OpenAPI
    url: openapi/brex-budgets-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/brex-webhooks-asyncapi.yml
- aid: brex:brex-spend-limits-api
  name: Brex Spend Limits API
  description: The Spend Limits API from Brex — 3 operation(s) for spend limits.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Spend Limits
  properties:
  - type: OpenAPI
    url: openapi/brex-spend-limits-api-openapi.yml
  - type: AsyncAPI
    url: asyncapi/brex-webhooks-asyncapi.yml
- aid: brex:brex-cards-api
  name: Brex Cards API
  description: Endpoints for card management.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Cards
  properties:
  - type: OpenAPI
    url: openapi/brex-cards-api-openapi.yml
- aid: brex:brex-companies-api
  name: Brex Companies API
  description: The Companies API from Brex — 1 operation(s) for companies.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Companies
  properties:
  - type: OpenAPI
    url: openapi/brex-companies-api-openapi.yml
- aid: brex:brex-cost-centers-api
  name: Brex Cost Centers API
  description: Endpoints for cost center management.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Cost Centers
  properties:
  - type: OpenAPI
    url: openapi/brex-cost-centers-api-openapi.yml
- aid: brex:brex-departments-api
  name: Brex Departments API
  description: Endpoints for department management.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Departments
  properties:
  - type: OpenAPI
    url: openapi/brex-departments-api-openapi.yml
- aid: brex:brex-legal-entities-api
  name: Brex Legal Entities API
  description: Endpoints for legal entities.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Legal Entities
  properties:
  - type: OpenAPI
    url: openapi/brex-legal-entities-api-openapi.yml
- aid: brex:brex-locations-api
  name: Brex Locations API
  description: Endpoints for location management.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Location
  tags_raw:
  - Locations
  properties:
  - type: OpenAPI
    url: openapi/brex-locations-api-openapi.yml
- aid: brex:brex-titles-api
  name: Brex Titles API
  description: Endpoints for title management.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - Titles
  properties:
  - type: OpenAPI
    url: openapi/brex-titles-api-openapi.yml
- aid: brex:brex-users-api
  name: Brex Users API
  description: Endpoints for user management.
  humanURL: https://developer.brex.com/openapi/budgets_api/
  tags:
  - User
  tags_raw:
  - Users
  properties:
  - type: OpenAPI
    url: openapi/brex-users-api-openapi.yml
name: Brex
tags:
- Bill Pay
- Corporate Cards
- Expenses
- Reimbursement
- Spending
- Accounting
- Expense Management
tags_raw:
- Bill Pay
- Corporate Cards
- Expenses
- Reimbursements
- Spending
- Accounting
- Expense Management
kind: contract
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: true
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Self-serve signup
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-11-06'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/brex.png
access: 3rd-Party
created: '2024-11-12'
modified: '2026-05-30'
position: Consuming
description: Brex is the first fully unified spend platform with global corporate cards, expense management, reimbursements,
  travel, and bill pay. Brex makes it easy for finance teams to control all of their spend, all in one place. Using the Brex
  API, you can power your internal tools and create custom workflows.
maintainers:
- FN: Kin Lane
  email: info@apievangelist.com
specificationVersion: '0.23'

Brex API — frequently asked questions

Does Brex have an API?

Yes. APIs.io lists 11 APIs from Brex, including Brex Budget Programs API, Brex Budgets API and Brex Spend Limits API, and 8 more.

Is there an OpenAPI specification for the Brex API?

Yes. APIs.io indexes 11 OpenAPI specifications for Brex, each linked for download from this page.

How do I authenticate with the Brex API?

Brex documents its authentication (http · 1 scheme). The details are profiled on APIs.io as Brex Authentication.

How much does the Brex API cost?

APIs.io lists 3 pricing plans for Brex, with each plan's price, limits and inclusions under Pricing on this page.

Does Brex have an MCP server?

Yes. APIs.io lists 1 MCP server for Brex: Remote MCP server at api.brex.com over HTTP.

Is the Brex API ready for AI agents?

Brex has a Kin Score of 22.7 out of 100 (emerging) and an Agent Readiness score of 53.0 (agent-ready), scored by API Evangelist on 2026-11-06.

Compared on APIs.io

Side by side with a competitor, using the compare_providers tool: facet by facet, with the full tool response.

vs Ramp Ramp vs Brex: the score and agent readiness disagree
All comparisons →

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for providers

9 MCP tools reach this

find_providersBrowse and filter every provider in the catalog.
get_provider_artifactsEvery artifact this provider publishes, grouped by type.
get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
get_provider_ratingPRO — composite, band, trend and facet scores.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

This provider

curl "https://apis.io/api/v1/providers/brex"

All providers

curl "https://apis.io/api/v1/providers?limit=25"

Every operation they expose

curl "https://apis.io/api/v1/providers/brex/operations?limit=25"

How their score was established

curl "https://apis.io/api/v1/providers/brex/evidence"

Calls without X-API-Key need no key. Calls with it need a paid plan — get a key.

Get an API key

Free tier, no form to fill in. Signing in shares your email address with us — we store it to create your key and to recognise you if you sign in with another provider. See our Privacy Policy and Terms.

GitHub Google LinkedIn

A second provider on the same verified email joins the account you already have.