Across website screenshot

Across

Across is a crosschain interoperability protocol powering fast, low-cost token transfers and swaps across 20+ EVM chains and Solana. Built on an intents-based design with a permissionless relayer network and UMA optimistic oracle settlement, Across fills crosschain transfers in roughly two seconds with no custodial risk. Developers integrate a single unified Swap API (plus embedded crosschain actions, gasless flows, and deposit tracking) to move native USDC, USDT, ETH, and other assets between Ethereum, Arbitrum, Base, Optimism, Polygon, Solana, and more. The protocol has facilitated over $36 billion in volume for 5M+ users. Across is a Paradigm portfolio company in the crypto-infrastructure sector.

Across publishes 1 API on the APIs.io network. Tagged areas include Company, Crypto Infrastructure, Cross-Chain, Bridge, and Interoperability.

Across’ developer surface includes documentation, API reference, getting-started guide, engineering blog, signup flow, authentication, and 11 more developer resources.

24.0/100 emerging ▬ flat Agent 11/100 agent aware saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0
1 APIs 1 MCP Servers
CompanyCrypto InfrastructureCross-ChainBridgeInteroperabilityBlockchainDeFiWeb3SwapPayments

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0
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 could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.
The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
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 github.com/api-evangelist/across: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 1

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

Across Swap API

The unified REST entry point for all crosschain operations on Across — request swap/bridge quotes and approval data, execute embedded crosschain actions on the destination chain...

MCP Servers 1

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

Across Protocol MCP Server

Official Across MCP server that indexes the Across documentation and exposes live Swap API operations as tools. Works with Claude Desktop, Claude Code, Cursor, Codex, and Windsu...

MCP SERVER

Security Posture 4

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

Across Authentication

2 schemes

SECURITY

Across Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Across Vulnerability Disclosure

contact published

SECURITY

Across Trust Center

trust center published

SECURITY

Resources

Get Started 2

Portal, sign-up, and the first successful call

Documentation 2

Reference material describing how the API behaves

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

Build 3

SDKs, sample code, and the tooling you integrate with

Access & Security 5

Authentication, authorization, and security posture

Company 2

The organization behind the API

Source (apis.yml)

apis.yml Raw ↑
aid: across
name: Across
description: Across is a crosschain interoperability protocol powering fast, low-cost token transfers and swaps across 20+
  EVM chains and Solana. Built on an intents-based design with a permissionless relayer network and UMA optimistic oracle
  settlement, Across fills crosschain transfers in roughly two seconds with no custodial risk. Developers integrate a single
  unified Swap API (plus embedded crosschain actions, gasless flows, and deposit tracking) to move native USDC, USDT, ETH,
  and other assets between Ethereum, Arbitrum, Base, Optimism, Polygon, Solana, and more. The protocol has facilitated over
  $36 billion in volume for 5M+ users. Across is a Paradigm portfolio company in the crypto-infrastructure sector.
url: https://raw.githubusercontent.com/api-evangelist/across/refs/heads/main/apis.yml
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: false
  label: Hosted service · you call their endpoint
  confidence: medium
  source:
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - authentication
  - security
  generated: '2026-09-03'
  method: derived
image: https://across.to/logo.svg
x-type: company
x-source: vc-portfolio
x-backed-by:
- paradigm
x-tier: profiled
x-tier-reason: enriched-from-public-surface
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-17'
tags:
- Company
- Crypto Infrastructure
- Cross-Chain
- Bridge
- Interoperability
- Blockchain
- DeFi
- Web3
- Swap
- Payments
tags_raw:
- Company
- Crypto Infrastructure
- Cross Chain
- Bridge
- Interoperability
- Blockchain
- DeFi
- Web3
- Swap
- Payments
apis:
- name: Across Swap API
  description: The unified REST entry point for all crosschain operations on Across — request swap/bridge quotes and approval
    data, execute embedded crosschain actions on the destination chain, run gasless flows, enumerate supported chains/tokens/sources,
    and track deposit lifecycle status. Authentication is a Bearer API key plus a 2-byte hex integratorId query parameter;
    testnet requires no credentials.
  humanURL: https://docs.across.to/introduction/swap-api
  baseURL: https://app.across.to/api
  tags:
  - Cross-Chain
  - Bridge
  - Swap
  - Payments
  tags_raw:
  - Cross Chain
  - Bridge
  - Swap
  - Payments
  properties:
  - type: Documentation
    url: https://docs.across.to
  - type: APIReference
    url: https://docs.across.to/api-reference
  - type: GettingStarted
    url: https://docs.across.to/introduction
  - type: Authentication
    url: authentication/across-authentication.yml
  - type: Conventions
    url: conventions/across-conventions.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/across-domain-security.yml
- type: Website
  url: https://across.to
- type: Documentation
  url: https://docs.across.to
- type: APIReference
  url: https://docs.across.to/api-reference
- type: GettingStarted
  url: https://docs.across.to/introduction
- type: Blog
  url: https://across.to/blog
- type: GitHubOrganization
  url: https://github.com/across-protocol
- type: SignUp
  url: https://docs.across.to/introduction/api-keys
- type: MCPServer
  url: mcp/across-mcp.yml
- type: SDKs
  url: packages/across-packages.yml
- type: Packages
  url: packages/across-packages.yml
- type: LLMsTxt
  url: llms/across-llms.txt
- type: Authentication
  url: authentication/across-authentication.yml
- type: Conventions
  url: conventions/across-conventions.yml
- type: VulnerabilityDisclosure
  url: security/across-vulnerability-disclosure.yml
- type: Security
  url: security/across-vulnerability-disclosure.yml
- type: TrustCenter
  url: security/across-trust-center.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence

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