Brex connector for AI agents

Tools your finance agent reaches for on Brex, scoped per user.

CALL ANY TOOL

68 tools for spend management in Brex: list card and cash transactions, create, lock, and unlock cards, set budgets and spend limits, update expense memos, manage vendors, and send transfers.

brex_budget_create

Create budget

Create a Brex budget that tracks spend against a target amount under a parent budget. Returns the new budget with its budget ID, name, parent, owners, period, amount, dates and status. Use this to set up a tracking budget. Use brex_spend_limit_create for a limit that controls card authorizations. Requires a parent budget ID from brex_budget_list.

Parameters

Name

Type

Required

Description

amount

integer

Required

Target amount the budget tracks, as an integer in the smallest unit of the currency (cents for USD). For example 150000 means $1,500.00. Example: 150000.

description

string

Required

What the budget is used for. Example: Cloud and tooling spend for the engineering team.

idempotency_key

string

Required

Unique key for this request, sent as the Idempotency-Key header that Brex requires on this endpoint. Generate a new value (for example a UUID) for each new operation, and reuse the same value only when retrying the same request, so Brex does not apply it twice. Example: 6f1c2b3a-9d4e-4f5a-8b7c-1d2e3f4a5b6c.

name

string

Required

Name of the budget. Example: Engineering Q3.

parent_budget_id

string

Required

ID of the parent budget this budget sits under. Get it from brex_budget_list. Example: budget_cl9rh1n8g001e0j84w6fb4fd1.

period_recurrence_type

string

Required

How often the budget period repeats: WEEKLY, MONTHLY, QUARTERLY, YEARLY, or ONE_TIME. Example: QUARTERLY. One of: `WEEKLY`, `MONTHLY`, `QUARTERLY`, `YEARLY`, `ONE_TIME`.

currency

string

Optional

ISO 4217 currency code for target amount the budget tracks. Brex defaults to USD when omitted. Example: USD.

end_date

string

Optional

Date (YYYY-MM-DD) the budget stops counting. Example: 2026-09-30.

limit_type

string

Optional

Whether the budget amount blocks spend. Only SOFT (track without blocking) is accepted here; HARD is rejected, so use brex_spend_limit_create for hard limits. Example: SOFT. One of: `SOFT`.

owner_user_ids

array

Optional

User IDs of the budget owners. Get IDs from brex_user_list. Example: ["cuuser_cky0xs54b004h01pidi0pcuz1"].

start_date

string

Optional

Date (YYYY-MM-DD) the budget starts counting. Example: 2026-07-01.

brex_budget_get

Get budget

brex_budget_list

List budget

brex_budget_update

Update budget

Update an existing Brex budget's name, description, parent, owners, period, amount or dates. Only the fields you provide change. Returns the updated budget. Use this to change a budget. Use brex_budget_get to read it first. Requires a budget ID from brex_budget_list.

Parameters

Name

Type

Required

Description

budget_id

string

Required

ID of the budget. Get it from brex_budget_list. Example: budget_cl9rh1n8g001e0j84w6fb4fd1.

idempotency_key

string

Required

amount

integer

Optional

New target amount the budget tracks, as an integer in the smallest unit of the currency (cents for USD). For example 150000 means $1,500.00. Leave empty to keep the current amount. Example: 150000.

currency

string

Optional

ISO 4217 currency code for the amount. Only used together with amount; Brex defaults to USD. Example: USD.

description

string

Optional

What the budget is used for. Leave empty to keep the current value. Example: Cloud and tooling spend for the engineering team.

end_date

string

Optional

Date (YYYY-MM-DD) the budget stops counting. Leave empty to keep the current value. Example: 2026-09-30.

limit_type

string

Optional

Whether the budget amount blocks spend. Only SOFT (track without blocking) is accepted here; HARD is rejected, so use brex_spend_limit_create for hard limits. Leave empty to keep the current value. Example: SOFT. One of: `SOFT`.

name

string

Optional

Name of the budget. Leave empty to keep the current value. Example: Engineering Q3.

owner_user_ids

array

Optional

User IDs of the budget owners. Get IDs from brex_user_list. Leave empty to keep the current value. Example: ["cuuser_cky0xs54b004h01pidi0pcuz1"].

parent_budget_id

string

Optional

ID of the parent budget this budget sits under. Get it from brex_budget_list. Leave empty to keep the current value. Example: budget_cl9rh1n8g001e0j84w6fb4fd1.

period_recurrence_type

string

Optional

How often the budget period repeats: WEEKLY, MONTHLY, QUARTERLY, YEARLY, or ONE_TIME. Leave empty to keep the current value. Example: QUARTERLY. One of: `WEEKLY`, `MONTHLY`, `QUARTERLY`, `YEARLY`, `ONE_TIME`.

start_date

string

Optional

Date (YYYY-MM-DD) the budget starts counting. Leave empty to keep the current value. Example: 2026-07-01.

brex_card_account_list

List card account

brex_card_get

Get card

brex_card_lock

Card lock

brex_card_statement_list

List card statement

brex_cash_account_list

List cash account

brex_cash_transaction_list

List cash transaction

brex_company_get

Get company

brex_custom_field_create

Create custom field

brex_custom_field_get

Get custom field

brex_custom_field_list

List custom field

brex_custom_field_update

Update custom field

brex_department_create

Create department

brex_department_get

Get department

brex_expense_list

List expense

List Brex expenses, filtered by user, budget, type, status, payment or compliance status, or purchase, update and payment dates. Returns a page of expenses with ID, memo, category, merchant, amounts, purchase date, status, payment status, budget and department/location/cost center IDs, optional expanded objects and custom fields, plus next_cursor. Use this to review or reconcile spend, or to find expenses missing receipts (compliance_status DUE or OVERDUE). Use brex_expense_get for one expense and brex_card_transaction_list for raw settled card transactions. Admins and bookkeepers see every expense; regular users see only their own.

Parameters

Name

Type

Required

Description

budget_ids

array

Optional

Only return expenses charged to these budgets or spend limits. Get IDs from brex_budget_list or brex_spend_limit_list. Example: ["budget_cl9rh1n8g001e0j84w6fb4fd1"].

compliance_status

array

Optional

Filter by documentation compliance status: DUE, OVERDUE, COMPLETED. Use DUE and OVERDUE to find expenses missing receipts, memos, attendees or coding. Example: ["DUE", "OVERDUE"].

cursor

string

Optional

Pagination cursor for the expense list. Pass the next_cursor value from the previous response to fetch the next page; omit it to start from the first page. A null next_cursor in a response means there are no more pages. Example: dXNlcl9jdXJzb3JfMTIz.

derived_compliance_status

array

Optional

Filter by combined documentation and review compliance: COMPLETED, DOCUMENTATION_DUE, REVIEW_DUE. Use DOCUMENTATION_DUE for expenses still missing submitter documentation. Example: ["DOCUMENTATION_DUE"].

expand

array

Optional

Related objects to include in full on each expense: location, department, cost_center, merchant, receipts.download_uris, user, budget, payment, spending_entity, policy. Example: ["merchant", "user"].

expense_types

array

Optional

Only return these expense types: CARD, BILLPAY, REIMBURSEMENT, CLAWBACK, UNSET. Example: ["CARD"].

limit

integer

Optional

Maximum number of expenses to return in one page, from 1 to 100. Leave empty to use the Brex default page size. Example: 50.

load_custom_fields

boolean

Optional

Set to true to include custom field values on each returned record. Leave empty or false to skip them for a smaller response. Example: true.

parent_expense_ids

array

Optional

Only return itemized expenses that belong to these parent expenses. Example: ["exp_xyz789"].

payment_posted_at_end

string

Optional

Only return expenses whose payment_posted_at is on or before this RFC 3339 date-time. Example: 2026-01-31T23:59:59Z.

payment_posted_at_start

string

Optional

Only return expenses whose payment_posted_at is on or after this RFC 3339 date-time. Example: 2026-01-01T00:00:00Z.

payment_status

array

Optional

Only return expenses with these payment statuses: NOT_STARTED, PROCESSING, CANCELED, DECLINED, CLEARED, REFUNDING, REFUNDED, CASH_ADVANCE, CREDITED, AWAITING_PAYMENT, SCHEDULED. Example: ["CLEARED"].

purchased_at_end

string

Optional

Only return expenses whose purchased_at is on or before this RFC 3339 date-time. Example: 2026-01-31T23:59:59Z.

purchased_at_start

string

Optional

Only return expenses whose purchased_at is on or after this RFC 3339 date-time. Example: 2026-01-01T00:00:00Z.

spending_entity_ids

array

Optional

Only return expenses attributed to these spending entities (legal entities). Get IDs from brex_legal_entity_list. Example: ["le_cl9rh1n8g001e0j84w6fb4fd1"].

status

array

Optional

Only return expenses in these statuses: DRAFT, SUBMITTED, APPROVED, OUT_OF_POLICY, VOID, CANCELED, SPLIT, SETTLED. Example: ["SUBMITTED", "OUT_OF_POLICY"].

updated_at_end

string

Optional

Only return expenses whose updated_at is on or before this RFC 3339 date-time. Example: 2026-01-31T23:59:59Z.

updated_at_start

string

Optional

Only return expenses whose updated_at is on or after this RFC 3339 date-time. Example: 2026-01-01T00:00:00Z.

user_ids

array

Optional

Only return expenses belonging to these users. Get IDs from brex_user_list or brex_current_user_get. Example: ["cuuser_cky0xs54b004h01pidi0pcuz1"].

brex_expense_update

Update expense

brex_legal_entity_get

Get legal entity

brex_linked_account_list

List linked account

brex_location_create

Create location

brex_spend_limit_get

Get spend limit

brex_spend_limit_list

List spend limit

brex_spend_limit_update

Update spend limit

Update an existing Brex spend limit's name, status, period, dates, limit amounts, visibility, merchant category controls, members or policies. Only the fields you provide change. Returns the updated spend limit. Use this to adjust a spend limit. Use brex_spend_limit_get to read it first. Requires a spend limit ID from brex_spend_limit_list.

Parameters

Name

Type

Required

Description

idempotency_key

string

Required

spend_limit_id

string

Required

ID of the spend limit. Get it from brex_spend_limit_list. Example: sl_cl9rh1n8g001e0j84w6fb4fd1.

allowed_merchant_categories

array

Optional

Only allow spend in these merchant categories, such as SOFTWARE, AIRLINE_EXPENSES or LODGING. Leave empty to keep the current setting. Example: ["SOFTWARE", "SERVERS"].

authorization_type

string

Optional

HARD declines card authorizations once the available balance is used; SOFT allows them. Leave empty to keep the current value. Example: HARD. One of: `HARD`, `SOFT`.

authorization_visibility

string

Optional

PUBLIC shows the limit amount to all members; PRIVATE shows it only to controllers, bookkeepers and owners. Leave empty to keep the current value. Example: PUBLIC. One of: `PUBLIC`, `PRIVATE`.

auto_create_limit_cards_setting

string

Optional

ALL_MEMBERS creates a limit card for every member automatically; DISABLED does not. Leave empty to keep the current value. Example: DISABLED. One of: `DISABLED`, `ALL_MEMBERS`.

auto_transfer_cards_setting

string

Optional

Whether virtual cards are transferred automatically: ENABLED or DISABLED. Leave empty to keep the current value. Example: DISABLED. One of: `DISABLED`, `ENABLED`.

base_limit_amount

integer

Optional

Base limit of the spend limit before increases or rollovers, as an integer in the smallest currency unit (cents for USD); 500000 means $5,000.00. Leave empty to keep the current value. Example: 500000.

base_limit_currency

string

Optional

ISO 4217 currency code for the base limit. Only used together with base_limit_amount; Brex defaults to USD. Example: USD.

blocked_merchant_categories

array

Optional

Block spend in these merchant categories, such as GAMBLING or BARS_NIGHTLIFE. Leave empty to keep the current setting. Example: ["GAMBLING"].

department_id

string

Optional

Department that expenses on this limit are attributed to. Get IDs from brex_department_list. Leave empty to keep the current value. Example: dept_cl9rh1n8g001e0j84w6fb4fd1.

description

string

Optional

What the spend limit is used for. Leave empty to keep the current value. Example: Flights and hotels for the sales team.

end_date

string

Optional

Date (YYYY-MM-DD) the spend limit expires. Leave empty to keep the current value. Example: 2026-12-31.

expense_policy_id

string

Optional

ID of the expense policy that applies to this spend limit. Find policy IDs in the Brex dashboard or on existing spend limits from brex_spend_limit_get. Leave empty to keep the current value. Example: policy_cl9rh1n8g001e0j84w6fb4fd1.

expense_visibility

string

Optional

SHARED lets all members see expenses on this limit; PRIVATE does not. Leave empty to keep the current value. Example: SHARED. One of: `SHARED`, `PRIVATE`.

legal_entity_id

string

Optional

Legal entity that expenses on this limit are attributed to. If not set, expenses go to the spending user's entity. Get IDs from brex_legal_entity_list. Leave empty to keep the current value. Example: le_cl9rh1n8g001e0j84w6fb4fd1.

limit_approval_policy_id

string

Optional

ID of the policy for limit increase approvals; replaces limit_increase_request_policy_id. Leave empty to keep the current value. Example: policy_cl9rh1n8g001e0j84w6fb4fd3.

limit_buffer_percentage

integer

Optional

Flexible buffer on top of the limit, as an integer from 0 to 100. Leave empty to keep the current value. Example: 10.

limit_increase_request_policy_id

string

Optional

ID of the policy for limit increase requests. Leave empty to keep the current value. Example: policy_cl9rh1n8g001e0j84w6fb4fd2.

limit_increase_setting

string

Optional

ENABLED lets members request limit increases; DISABLED does not. Leave empty to keep the current value. Example: ENABLED. One of: `ENABLED`, `DISABLED`.

member_user_ids

array

Optional

User IDs of the members who can spend from this limit. Leave empty to keep the current value. Example: ["cuuser_cky0xs54b004h01pidi0pcuz1"].

name

string

Optional

Name of the spend limit. Leave empty to keep the current value. Example: Team travel.

owner_user_ids

array

Optional

User IDs of the spend limit owners. Get IDs from brex_user_list. Leave empty to keep the current value. Example: ["cuuser_cky0xs54b004h01pidi0pcuz1"].

period_recurrence_type

string

Optional

How often the limit resets: PER_WEEK, PER_MONTH, PER_QUARTER, PER_YEAR, or ONE_TIME. Leave empty to keep the current value. Example: PER_MONTH. One of: `PER_WEEK`, `PER_MONTH`, `PER_QUARTER`, `PER_YEAR`, `ONE_TIME`.

rollover_refresh_rate

string

Optional

How unused funds roll over: OFF (no rollover), NEVER (roll over indefinitely), or PER_MONTH, PER_QUARTER, PER_YEAR (rolled-over funds reset at that interval). Leave empty to keep the current value. Example: OFF. One of: `OFF`, `NEVER`, `PER_MONTH`, `PER_QUARTER`, `PER_YEAR`.

set_end_date_null

boolean

Optional

Set to true to remove the expiry date. Example: true.

set_start_date_null

boolean

Optional

Set to true to remove the start date. Example: true.

set_transaction_limit_null

boolean

Optional

Set to true to remove the per-transaction limit. Example: true.

spend_type

string

Optional

BUDGET_PROVISIONED_CARDS_ONLY allows spend only from cards provisioned by this limit; NON_BUDGET_PROVISIONED_CARDS_ALLOWED also allows other cards. Leave empty to keep the current value. Example: BUDGET_PROVISIONED_CARDS_ONLY. One of: `BUDGET_PROVISIONED_CARDS_ONLY`, `NON_BUDGET_PROVISIONED_CARDS_ALLOWED`.

start_date

string

Optional

Date (YYYY-MM-DD) the spend limit starts counting. Leave empty to keep the current value. Example: 2026-07-01.

status

string

Optional

New status for the spend limit: ACTIVE, EXPIRED, ARCHIVED, or DELETED. Leave empty to keep the current status. Example: ACTIVE. One of: `ACTIVE`, `EXPIRED`, `ARCHIVED`, `DELETED`.

transaction_limit_amount

integer

Optional

Maximum amount allowed per transaction, as an integer in the smallest unit of the currency (cents for USD). For example 150000 means $1,500.00. Leave empty for no per-transaction limit change. Example: 150000.

transaction_limit_currency

string

Optional

ISO 4217 currency code for the transaction limit. Only used together with transaction_limit_amount; Brex defaults to USD. Example: USD.

brex_title_create

Create title

brex_transfer_get

Get transfer

brex_transfer_list

List transfer

brex_trip_get

Get trip

brex_trip_list

List trip

For more tools, view docs.

Build your Agent

Same auth pattern across LangChain, OpenAI, Anthropic, and Google ADK.

import { ScalekitClient } from "@scalekit-sdk/node";
import { createReactAgent } from "@langchain/langgraph/prebuilt";

const sk = new ScalekitClient(env.SCALEKIT_ENV_URL, env.SCALEKIT_CLIENT_ID, env.SCALEKIT_CLIENT_SECRET);

// Brex tools scoped to this user
const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["brex"], toolNames: [
    "brex_expense_list",
    "brex_expense_update",
    "brex_card_transaction_list"] },
  pageSize: 100,
});

const agent = createReactAgent({ llm, tools });
await agent.invoke({ messages: [{ role: "user", content: "Find card expenses over $500 this month that are missing a memo" }] });

import OpenAI from "openai";
import { ScalekitClient } from "@scalekit-sdk/node";

const sk = new ScalekitClient(env.SCALEKIT_ENV_URL, env.SCALEKIT_CLIENT_ID, env.SCALEKIT_CLIENT_SECRET);
const openai = new OpenAI();

const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["brex"] }, pageSize: 100,
});

const res = await openai.chat.completions.create({
  model: "gpt-5",
  messages: [{ role: "user", content: "Find card expenses over $500 this month that are missing a memo" }],
  tools,
});

// Execute the tool call with the user's vaulted Brex OAuth token
await sk.tools.executeTool(res.choices[0].message.tool_calls[0], "user_123");

import Anthropic from "@anthropic-ai/sdk";
import { ScalekitClient } from "@scalekit-sdk/node";

const sk = new ScalekitClient(env.SCALEKIT_ENV_URL, env.SCALEKIT_CLIENT_ID, env.SCALEKIT_CLIENT_SECRET);
const anthropic = new Anthropic();

const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["brex"] }, pageSize: 100,
});

const msg = await anthropic.messages.create({
  model: "claude-sonnet-5",
  max_tokens: 1024,
  messages: [{ role: "user", content: "Find card expenses over $500 this month that are missing a memo" }],
  tools,
});

// Tool call runs with the user's vaulted Brex OAuth token
await sk.tools.executeTool(msg.content, "user_123");

import { Agent } from "@google/adk/agents";
import { ScalekitClient } from "@scalekit-sdk/node";

const sk = new ScalekitClient(env.SCALEKIT_ENV_URL, env.SCALEKIT_CLIENT_ID, env.SCALEKIT_CLIENT_SECRET);

const { tools } = await sk.tools.listScopedTools("user_123", {
  filter: { connectionNames: ["brex"] }, pageSize: 100,
});

const agent = new Agent({
  name: "spend_agent",
  model: "gemini-2.5-pro",
  instruction: "Brex tools scoped to this user",
  tools,
});

await agent.run("Find card expenses over $500 this month that are missing a memo");

Try these prompts

Copy any prompt into your agent. Each maps directly to a Brex tool. Click to copy, paste into your agent, done.

Cards and transactions

Copy the prompt

Copied

List card transactions over $1,000 from the last 7 days.

Copy the prompt

Copied

Lock the card ending 4412 until finance reviews it.

Copy the prompt

Copied

Create a virtual card for Priya Shah.

Budgets and expenses

Copy the prompt

Copied

Show the Marketing budget and the spend limits under it.

Copy the prompt

Copied

List expenses that are out of policy this month.

Copy the prompt

Copied

Add the memo 'Client dinner, Acme renewal' to this expense.

Vendors and transfers

Copy the prompt

Copied

List outgoing transfers from our primary cash account this month.

Copy the prompt

Copied

Add Northwind Supply as a vendor with their ACH details.

Copy the prompt

Copied

Send $4,800 to Northwind Supply from our primary cash account.

SEE HOW AUTH WORKS

Each user signs in to Brex once, and Scalekit stores and refreshes their tokens. Credentials stay vaulted, every call is scope checked, and every action is logged.

Authorize

Your user connects

Brex

once. We tie it to their identity and the meetings they approved — no shared bot account, no org-wide access

Who:

user ‘A’

when:

Once per user

access:

Limited to user

Store

Their

Brex

token lives in a vault scoped to them. User A's meetings are never reachable by an agent acting for user B, even on the same connection

vault:

encrypted

scope:

per-user

tokens:

auto-refreshed

Resolve

When your agent calls a

Brex

tool, we fetch the right token server-side. It never touches your agent, never appears in the LLM context, never shows up in your logs

speed:

~40ms

check:

before every call

seen by:

nobody

Audit

Every

Brex

tool call is logged — who triggered it, which meeting was fetched, what came back. 90 days of history, tied to the user who authorized it

history:

90 days

export:

SIEM-ready

logged:

every call

Test other agents

See the same per-user auth pattern across other accounting and finance connectors.

GTM and RevOps Teams

Revenue forecast commentary

Pulls open pipeline from Salesforce and HubSpot, calculates coverage against quota, flags at-risk stages, posts commentary to Slack, and logs every snapshot to Google Sheets.

Engineering Teams

Slack triage

Polls Slack for new messages, classifies bugs and support requests with a LangGraph router, files GitHub issues or Zendesk tickets, and confirms in the thread.

Why Scalekit

Secure your agent's access. Connectors ship in minutes

01.

Shared tokens break per-user analytics

A shared Brex token looks fine in a demo. In production every card lock and transfer looks like one service account, and you cannot tell which user triggered it. Scalekit resolves the credential of the actual user who triggered the agent, never a shared bot.

// shared token
audit → bot_service_account

// scalekit
audit → user_abc ✓

02.

Authentication is not authorization

03.

Multi-tenancy is architectural

04.

Brex today. Ten connectors tomorrow.

“Our agents act across Salesforce, Gong, Google Drive, and more, on behalf of every customer. Scalekit behind the scenes meant we can keep adding tools without ever rebuilding how credentials or tool calling work.”

Venu Madhav Kattagoni

Head of Engineering / Von

FAQs

Frequently Asked Questions

Does the agent access Brex as the user or through a shared service account?

As the user. Each user signs in to Brex once, and Scalekit stores and refreshes their tokens. Card changes, budget updates, and transfers the agent makes are attributed to that user in your audit trail, not a shared service account.

Where is the Brex OAuth token stored?

In Scalekit's managed AES-256 token vault, namespaced per tenant. Refresh is automatic. Revocation is a single dashboard action. Credentials never appear in prompts, logs, or LLM context.

Can I limit what the agent does in Brex?

Yes. Filter by tool name in listScopedTools to expose only what you want, for example the list and get tools for transactions, budgets, and expenses without brex_transfer_create, which sends money from a Brex business account to a vendor. Scalekit also enforces scope checks before every API call.

What happens when a user revokes Brex access?

The connection is invalidated on the next tool call. Subsequent requests for that user fail closed with a clear error. Other users in the tenant remain unaffected. The event is logged for audit.

Which Brex account does the agent work on?

The Brex company the signed-in user belongs to. brex_company_get returns that company and brex_current_user_get returns the user who authorized the connection. Card, budget, expense, and transfer tools act on that company's accounts.