# Atum Docs

- [What is Atum?](https://docs.atum.xyz/get-started/overview/what-is-atum.md): The open payments network for an open world.
- [Atum payment lifecycle](https://docs.atum.xyz/get-started/overview/how-an-atum-payment-works.md): A payment goes through five stages: request, accept, select, deliver, confirm.
- [Treasury management](https://docs.atum.xyz/get-started/use-cases/treasury-management.md): Move liquidity across payment rails and subsidiary treasuries — without correspondent banking fees, complexity, or delays.
- [Payouts](https://docs.atum.xyz/get-started/use-cases/payouts.md): Send tokenized currency to contractors, gig workers, or any recipient — on whatever rail and in whatever token they hold.
- [Merchant acceptance](https://docs.atum.xyz/get-started/use-cases/merchant-acceptance.md): Accept any tokenized currency from your buyers — regardless of which rail or token they're sending from.
- [Agentic payouts](https://docs.atum.xyz/get-started/use-cases/agentic-payouts.md): Atum is the payment tool your agent calls when a decision requires funds to move — what the agent decides, and what still has to be signed.
- [Atum infrastructure](https://docs.atum.xyz/get-started/architecture/payment-rails-primer.md): A two-minute orientation on how Atum's payment infrastructure differs from traditional rails — no blockchain background needed.
- [Core concepts](https://docs.atum.xyz/get-started/architecture/core-concepts.md): Key ideas to understand before you integrate — browse by topic below.
- [What is Atum ID?](https://docs.atum.xyz/get-started/identity/overview.md): Identity on a payment, not a login — and not permission to move funds.
- [What is Atum ID?](https://docs.atum.xyz/get-started/identity/overview.md): Identity on a payment, not a login — and not permission to move funds.
- [Know Your Agent](https://docs.atum.xyz/get-started/identity/know-your-agent.md): Who is answerable when software spends on your behalf.
- [Credentials](https://docs.atum.xyz/get-started/identity/credentials.md): What 'credential' means if you come from cards or wallets
- [Verifiable presentations](https://docs.atum.xyz/get-started/identity/verifiable-presentation.md): The W3C wrapper that binds credentials to a specific payment or quote.
- [Payment request](https://docs.atum.xyz/get-started/concepts/payment-intent.md): What a payment request is, what you sign, and what happens after you submit it.
- [Idempotency](https://docs.atum.xyz/payment-protocols/idempotency.md): How Atum deduplicates retries so a payment or quote request is never created twice.
- [Policy enforcement](https://docs.atum.xyz/get-started/concepts/policy-enforcement.md): Two ways to constrain who may fulfill a payment.
- [Network participants](https://docs.atum.xyz/get-started/concepts/participants.md): Who does what in an Atum payment — your app, the gateway, settlement providers, and recipients.
- [Corridors and assets](https://docs.atum.xyz/get-started/concepts/corridors-and-assets.md): Which rail and token pairs are supported, how assets are identified, and how amounts work.
- [Token approvals](https://docs.atum.xyz/get-started/concepts/permit2-and-approvals.md): One-time setup that lets Atum move tokens from your source account before a payment.
- [Prerequisites](https://docs.atum.xyz/get-started/start-building/prerequisites.md): What your wallet needs before making a real Atum payment — funds, gas, and allowances for the payer, and a valid receive address for the recipient. Applies whether you use the CLI, the SDK, or the payment-protocol examples.
- [Using the CLI](https://docs.atum.xyz/get-started/start-building/using-the-cli.md): Send your first testnet payment through the Payment Gateway CLI.
- [Build with the SDK](https://docs.atum.xyz/get-started/start-building/build-with-the-sdk.md): Submit a multi-rail sandbox payment with the Payment Gateway Client SDK. Includes raw HTTP submit/status examples; building the unsigned payment is done with the SDK or CLI.
- [Who owns what](https://docs.atum.xyz/get-started/support/who-owns-what.md): What Atum secures versus what payment and settlement providers own in the network.
- [Troubleshooting](https://docs.atum.xyz/get-started/support/troubleshooting.md): Common errors — payment not settling, stuck payments, and payment authorization.
- [Reconciliation](https://docs.atum.xyz/get-started/support/reconciliation.md): The identifiers and fields to record for every payment so you can reconcile it without reconstructing it from wallet dashboards — and how to separate Atum fees from gas, swap, and bridge costs.
- [Endpoints](https://docs.atum.xyz/get-started/reference/endpoints.md): Canonical base URLs for Atum's hosted services on testnet and mainnet.
- [Supported networks](https://docs.atum.xyz/get-started/reference/supported-networks.md): Networks configured for support on Atum's Payment Gateway, plus contract and token addresses.
- [Supported assets](https://docs.atum.xyz/get-started/reference/supported-assets.md): Tokenized money supported on Atum's Payment Gateway, organized by asset type.
- [Contract addresses](https://docs.atum.xyz/get-started/reference/contract-addresses.md): Protocol contracts deployed on Atum's supported networks.
- [Glossary](https://docs.atum.xyz/get-started/reference/glossary.md): Definitions for Atum Protocol terms used across the documentation.
- [Testnet wallet setup](https://docs.atum.xyz/get-started/reference/setup-testnet-wallet.md): Fund an EVM wallet on Arbitrum Sepolia to follow along with the CLI quickstart.
- [Security Reviews](https://docs.atum.xyz/security-reviews.md): Independent security reviews of Atum settlement contracts,
- [Payment protocols](https://docs.atum.xyz/payment-protocols/overview.md): Choosing between x402 and MPP for agentic HTTP payments.
- [Choose an environment](https://docs.atum.xyz/payment-protocols/environments.md): Which environment to use when running the x402 and MPP payment examples — local stub, hosted testnet, and mainnet.
- [Pre-flight checklist](https://docs.atum.xyz/payment-protocols/pre-flight-checklist.md): Run through this before switching the x402 or MPP examples off the stub and settling a real payment on testnet or mainnet.
- [Atum x402: Overview](https://docs.atum.xyz/payment-protocols/x402/overview.md): Coordinate programmatic payments using Atum
- [Make payments using Atum and x402](https://docs.atum.xyz/payment-protocols/x402/make-payments/overview.md): Pay for x402-gated HTTP resources from your agent.
- [Agentic sends](https://docs.atum.xyz/payment-protocols/x402/make-payments/agentic-payment-initiation.md): Run a working x402 payment client locally — the same flow an autonomous agent follows to pay for a gated resource.
- [Develop with Atum SDK](https://docs.atum.xyz/payment-protocols/x402/make-payments/develop-with-the-sdk.md): Integrate x402 payment initiation directly into your agent's code with the @atumlabs/x402-atum-escrow client package.
- [Accept payments using Atum and x402](https://docs.atum.xyz/payment-protocols/x402/accept-payments/overview.md): Gate an HTTP route or agent-facing tool behind an x402 payment, settled through Atum.
- [Agentic receives](https://docs.atum.xyz/payment-protocols/x402/accept-payments/agentic-payment-acceptance.md): Run a working x402 merchant server locally — gate a route the way you'd charge an AI agent for an API call or tool use.
- [Develop with Atum SDK](https://docs.atum.xyz/payment-protocols/x402/accept-payments/develop-with-the-sdk.md): Gate your own route, tool, or API behind x402 payment with the @atumlabs/x402-atum-escrow server package.
- [Atum and MPP: Overview](https://docs.atum.xyz/payment-protocols/mpp/overview.md): Pay for or gate agent-facing resources using the Machine Payments Protocol (MPP) and Atum.
- [Make payments using Atum and MPP](https://docs.atum.xyz/payment-protocols/mpp/make-payments/overview.md): Pay for MPP-gated HTTP resources from your agent.
- [Agentic sends](https://docs.atum.xyz/payment-protocols/mpp/make-payments/agentic-payment-initiation.md): Run a working MPP payment client locally — the same flow an autonomous agent follows to pay for a gated resource.
- [Develop with Atum SDK](https://docs.atum.xyz/payment-protocols/mpp/make-payments/develop-with-the-sdk.md): Register Atum's MPP payment method with mppx and pay for MPP-gated resources directly from your agent's code.
- [Accept payments using Atum and MPP](https://docs.atum.xyz/payment-protocols/mpp/accept-payments/overview.md): Gate an HTTP route or agent-facing tool behind an MPP payment with Atum.
- [Agentic receives](https://docs.atum.xyz/payment-protocols/mpp/accept-payments/agentic-payment-acceptance.md): Run a working MPP merchant server locally — gate a route the way you'd charge an AI agent for an API call or tool use.
- [Develop with Atum SDK](https://docs.atum.xyz/payment-protocols/mpp/accept-payments/develop-with-the-sdk.md): Register Atum's MPP payment method with mppx and accept MPP payments directly in your server's code.
- [What is an Atum settlement?](https://docs.atum.xyz/settle-payments/what-is-an-atum-settlement.md): How settlements work on Atum's open payments network.
- [The settlement lifecycle](https://docs.atum.xyz/settle-payments/settlement-lifecycle.md): The settlement flow from quote selection to completion.
- [Operating a settler agent](https://docs.atum.xyz/settle-payments/operating-a-settler-agent.md): The reference agent for fulfilling settlements on Atum.
- [Present identity with a quote](https://docs.atum.xyz/settle-payments/presenting-identity.md): How a settlement provider presents Known to Atum when submitting a price quote — available, not required by default.
- [Integration guide](https://docs.atum.xyz/settle-payments/integration-guide.md): Deploy and run a settler agent on your own infrastructure.
- [Test a settlement flow](https://docs.atum.xyz/settle-payments/testnet.md): Run an end-to-end settlement on testnet before deploying to mainnet.
- [Bidding strategies](https://docs.atum.xyz/settle-payments/bidding-strategies.md): Configure how a settler agent prices and submits quotes to payment requests.
- [Configuration overview](https://docs.atum.xyz/settle-payments/configuration/overview.md): Directory structure, environment variables, and profile configuration for a settler agent.
- [Configuration overview](https://docs.atum.xyz/settle-payments/configuration/overview.md): Directory structure, environment variables, and profile configuration for a settler agent.
- [RPC endpoints](https://docs.atum.xyz/settle-payments/configuration/rpc-endpoints.md): Configure blockchain RPC access for testnet and production.
- [Databases](https://docs.atum.xyz/settle-payments/configuration/databases.md): Provision and connect the PostgreSQL database a settler agent depends on.
- [Volume mounts](https://docs.atum.xyz/settle-payments/configuration/volume-mounts.md): Mount profile and plugin configuration into the settler agent container.
- [Production deployments](https://docs.atum.xyz/settle-payments/configuration/production-deployments.md): Recommended resources and scaling for running a settler agent in production.
- [Best practices](https://docs.atum.xyz/settle-payments/configuration/best-practices.md): Security best practices for operating a settler agent.
- [Endpoints](https://docs.atum.xyz/get-started/reference/endpoints.md): Canonical base URLs for Atum's hosted services on testnet and mainnet.
- [Supported testnets](https://docs.atum.xyz/settle-payments/supported-testnets.md): Testnet networks, assets, and faucets for settler agents.
- [Supported mainnets](https://docs.atum.xyz/settle-payments/supported-mainnets.md): Mainnet networks and assets accepted for settlement on Atum.
- [Agent error reference](https://docs.atum.xyz/settle-payments/error-reference.md): The error codes your settler agent writes to its own logs, what each one means, and what to do about it.
- [Glossary](https://docs.atum.xyz/get-started/reference/glossary.md): Definitions for Atum Protocol terms used across the documentation.
- [Security Reviews](https://docs.atum.xyz/security-reviews.md): Independent security reviews of Atum settlement contracts,
- [Overview](https://docs.atum.xyz/api-reference/payment-gateway/introduction.md): Secure, cross-chain payments with built-in escrow protection and settlement verification
- [Submit payment request](https://docs.atum.xyz/api-reference/payment-gateway/submit-payment.md): Submit a signed payment request to the Atum Payment Gateway. request_id is the idempotency key that makes a retry safe.
- [Get payment status](https://docs.atum.xyz/api-reference/payment-gateway/get-payment-status.md): Poll a payment's current status by payment_id: pending, completed, or failed.
- [Resolve a payment request](https://docs.atum.xyz/api-reference/payment-gateway/resolve-payment.md): Look a payment up by the request_id you submitted, for when you lost the submit response but kept your idempotency key.
- [Get payment timeline](https://docs.atum.xyz/api-reference/payment-gateway/payment-timeline.md): Read the step-by-step settlement record for one payment. Use it for reconciliation and support, not to decide what to do next.
- [Create a quote-request](https://docs.atum.xyz/api-reference/payment-gateway/create-quote-request.md): Open a quote-request batch and collect price quotes for a corridor, without committing to a payment.
- [Get quote-request status](https://docs.atum.xyz/api-reference/payment-gateway/quote-request-status.md): Read a quote-request batch and the quotes collected for it so far.
- [Get chain defaults](https://docs.atum.xyz/api-reference/payment-gateway/chain-defaults.md): Fetch the Payment Gateway's live chain defaults: contract addresses per CAIP-2 chain, and which chains you can actually pay on, instead of hardcoding them.
- [Overview](https://docs.atum.xyz/api-reference/x402/introduction.md): The standard x402 v2 facilitator interface served by atum-escrow
- [Verify payment](https://docs.atum.xyz/api-reference/x402/verify.md): Checks the credential against the selected requirement: the PaymentRequestEnvelope identity binding (a holder-signed verifiable presentation whose proofPurpose is 'authentication', whose proof.challenge equals the request's request_hash, whose proof.domain is the network-wide verifier id, and whose…
- [Settle payment](https://docs.atum.xyz/api-reference/x402/settle.md): Submits the request to the Atum network for settlement and resolves synchronously when the payment is delivered, within the requirement's maxTimeoutSeconds. Returns the settlement transaction and network plus the settlement receipt (also carried to the payer in the PAYMENT-RESPONSE header). Asynchro…
- [Supported kinds](https://docs.atum.xyz/api-reference/x402/supported.md)
- [Error codes](https://docs.atum.xyz/errors.md): Every error code the Atum APIs return, what each one means, and what to do about it. Branch on the code rather than the message text.
- [Decline reasons](https://docs.atum.xyz/decline-reasons.md): Why a settlement provider did not quote on a payment, what each reason means, and what would change it. A decline is not a payment failure.

## OpenAPI Specs

- [error-openapi](/api-reference/common/error-openapi.yaml)
- [openapi](/api-reference/payment-gateway/openapi.yaml)
- [openapi](/api-reference/x402/openapi.yaml)