> ## Documentation Index > Fetch the complete documentation index at: https://docs.eco.com/llms.txt > Use this file to discover all available pages before exploring further. # List chains > Returns every chain the API can quote, with Portal and Executor addresses and the quote-signing address. Returns every chain the API can quote, with its Portal and Executor contract addresses and the address that signs quotes. `chainId` filters to one chain. Solana is chain `1399811149`. Requires `x-api-key`. Partner pricing, attribution, and enabled features are tied to the key. Without a key the gateway answers `403` with a plain JSON body (`{"Message": "User is not authorized ..."}`); a key that is unknown, revoked, or not enabled for v1 answers `401 invalid-api-key`. No requests-per-second quota is published. Handle `429` and honor `Retry-After` when present. Examples use real mainnet token and contract addresses with placeholder wallets, hashes, signatures, and IDs. ## OpenAPI ````yaml api-v1.openapi.json GET /v1/chains openapi: 3.1.0 info: title: Eco API version: v1 description: >- Reference for the Eco API at https://api.eco.com/v1: quotes, chain and token discovery, gasless funding, intent status, and Circle Gateway fast deposits. Every operation requires an API key except the Circle Gateway operations, which are open. servers: - url: https://api.eco.com description: Eco API security: [] tags: - name: quotes - name: intents - name: status - name: discovery - name: circle-gateway paths: /v1/chains: get: tags: - discovery summary: List chains description: >- Returns every chain the API can quote, with its Portal and Executor contract addresses and the address that signs quotes. `chainId` filters to one chain. Solana is chain `1399811149`. Requires `x-api-key`. Partner pricing, attribution, and enabled features are tied to the key. Without a key the gateway answers `403` with a plain JSON body (`{"Message": "User is not authorized ..."}`); a key that is unknown, revoked, or not enabled for v1 answers `401 invalid-api-key`. No requests-per-second quota is published. Handle `429` and honor `Retry-After` when present. Examples use real mainnet token and contract addresses with placeholder wallets, hashes, signatures, and IDs. operationId: chains.list parameters: - name: chainId in: query required: false schema: type: integer exclusiveMinimum: 0 description: 'Returns only this chain. Example: `8453` for Base.' example: 8453 responses: '200': description: Success content: application/json: schema: type: object properties: chains: type: array items: type: object properties: chainId: type: integer name: type: string quoteSigner: description: >- Address whose EIP-712 signature appears as `signature` on every quote for this chain. Read it from here and cache with a refresh rather than pinning it; it can rotate. type: string type: type: string enum: - evm - svm - tvm encoding: type: string enum: - abi - borsh status: type: string enum: - live - paused contracts: type: object properties: portal: type: string description: >- Address on the relevant chain: `0x…` hex for EVM chains, base58 for Solana, `T…` base58 for Tron. executor: type: - string - 'null' description: >- Address on the relevant chain: `0x…` hex for EVM chains, base58 for Solana, `T…` base58 for Tron. required: - portal - executor description: >- Deployed Eco contracts: `portal` is the funding target for this chain's intents, `executor` runs destination calls (null where not deployed). required: - chainId - name - quoteSigner - type - encoding - status - contracts limits: type: object properties: paging: type: object properties: maxLimit: type: integer defaultLimit: type: integer required: - maxLimit - defaultLimit required: - paging required: - chains examples: all-chains: summary: Live response on 2026-09-15 value: chains: - chainId: 1 name: Ethereum quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 10 name: OP Mainnet quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 130 name: Unichain quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 137 name: Polygon quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 143 name: Monad quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: null - chainId: 480 name: World Chain quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 999 name: HyperEVM quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 2020 name: Ronin quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 5042 name: Arc quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: null - chainId: 8453 name: Base quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 9745 name: Plasma quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 42161 name: Arbitrum One quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' - chainId: 1399811149 name: Solana quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: svm encoding: abi status: live contracts: portal: EcooswwC1NggsckZyF5SeAL9WsgJs3UhPbrqY1apV73F executor: Gk1ZpHHx9tgSo68hiT2prBQCjkstdUYVZn4SWL3NzR2U limits: paging: maxLimit: 50 defaultLimit: 20 one-chain: summary: GET /v1/chains?chainId=8453 value: chains: - chainId: 8453 name: Base quoteSigner: '0x1D636584Eec22B53Be1930daF6B12a0E13C8B870' type: evm encoding: abi status: live contracts: portal: '0xEC000064576f9C95a8623Bc0eff3db6d296ea6df' executor: '0xEc2C96e75B09e29b66bf2Ee5C37fa749eF9AA7c7' limits: paging: maxLimit: 50 defaultLimit: 20 '400': description: Request failed validation content: application/problem+json: schema: $ref: '#/components/schemas/Problem' example: type: https://api.eco.com/v1/errors/invalid-request title: Request failed validation status: 400 code: invalid-request requestId: f371e43e6fd4406b10e19487b3170edf '401': description: >- The supplied x-api-key is unknown, revoked, or not enabled for the v1 API. Returned for every v1 endpoint by the gateway, with Content-Type application/json. content: application/json: schema: $ref: '#/components/schemas/Problem' example: type: https://api.eco.com/v1/errors/invalid-api-key title: API key is missing, unknown, or revoked status: 401 code: invalid-api-key requestId: 98e4c42f-9c70-4539-843e-8d31803001e6 '403': description: >- No API key supplied. The gateway rejects the request before it reaches the API, with a plain JSON body. content: application/json: example: Message: >- User is not authorized to access this resource with an explicit deny in an identity-based policy '429': description: Rate limit exceeded content: application/problem+json: schema: $ref: '#/components/schemas/Problem' example: type: https://api.eco.com/v1/errors/rate-limit-exceeded title: Rate limit exceeded status: 429 code: rate-limit-exceeded requestId: 1eac3d6cc2aafa524b0c47a039576f8c '500': description: Internal error content: application/problem+json: schema: $ref: '#/components/schemas/Problem' example: type: https://api.eco.com/v1/errors/internal-error title: Internal error status: 500 code: internal-error requestId: 02dabcf0f4e3def9a6091526d3d21022 default: description: Error (RFC 9457 problem+json; see x-error-catalog) content: application/problem+json: schema: $ref: '#/components/schemas/Problem' security: - ApiKey: [] components: schemas: Problem: type: object properties: type: type: string format: uri title: type: string minLength: 1 status: type: integer minimum: 400 maximum: 599 code: type: string description: >- Stable, machine-readable error code from the catalog. Branch on this and `status`, not on `title` or `detail`. detail: type: string instance: type: string legacyCode: type: string description: >- The pre-v1 numeric error code this problem maps to, for integrations migrating from the older services. solverErrors: type: array items: type: object properties: solver: type: string description: >- Address on the relevant chain: `0x…` hex for EVM chains, base58 for Solana, `T…` base58 for Tron. solverName: type: string minLength: 1 code: type: string minLength: 1 message: type: string required: - solver - message errors: type: array items: type: object properties: field: type: string minLength: 1 detail: type: string minLength: 1 required: - field - detail description: Field-level validation failures. requestId: type: string description: >- Correlation ID for support. Present on router-served errors; deposit-address-served errors carry a short numeric value. required: - type - title - status - code securitySchemes: ApiKey: type: apiKey in: header name: x-api-key ````