Optimism
Optimism is an Ethereum Layer 2 scaling network and the originator of the OP Stack — an open-source, modular rollup framework that powers OP Mainnet and a growing Superchain of interoperable chains (Base, Mode, Zora, Worldchain, and others). Developers interact via standard Ethereum JSON-RPC, the Optimism (Viem-based) SDK, the canonical Optimism Bridge, OP Stack operator tooling (op-geth, op-node, op-deployer, op-batcher, op-proposer, op-challenger), and the Superchain Registry.
Optimism publishes 3 APIs on the APIs.io network: OP Mainnet JSON-RPC, OP Sepolia JSON-RPC, and JSON-RPC API. Tagged areas include Layer 2, Ethereum, OP Stack, Superchain, and JSON-RPC.
The Optimism catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.
Optimism’s developer surface includes documentation, GitHub presence, status page, engineering blog, and 10 more developer resources.
Kin Score
APIs 10
Individual APIs this provider publishes, each with its own machine-readable definition.
OP Mainnet JSON-RPC
Public Ethereum JSON-RPC endpoint for OP Mainnet (chain ID 10). Supports standard eth_* methods plus Optimism extensions for L1 fee estimation, deposit tracking, and withdrawal ...
OP Sepolia JSON-RPC
Public Ethereum JSON-RPC endpoint for the OP Sepolia testnet (chain ID 11155420) used for development and integration testing.
Optimism Bridge (Standard Bridge)
Canonical cross-chain bridge for depositing and withdrawing ETH and ERC-20 tokens between Ethereum L1 and OP Mainnet, secured by the OP Stack StandardBridge contracts. Available...
OP Stack
Open-source, modular Ethereum L2 rollup stack. The monorepo at github.com/ethereum-optimism/optimism contains op-geth (execution), op-node (consensus), op-batcher, op-proposer, ...
Superchain Registry
Source-of-truth index of chains that are part of the Optimism Superchain — genesis files, deployment addresses, RPC endpoints, explorers, and chain metadata in machine-readable ...
Optimism SDK (Viem extension)
Modern Optimism SDK exposed as a Viem extension (viem/op-stack) for L1<->L2 message tracking, deposit and withdrawal flows, fee estimation, and Superchain multi-chain helpers.
Supersim
Local Superchain simulator that spins up multiple OP Stack chains for developing and testing cross-chain interop messages (CrossL2Inbox / L2ToL2CrossDomainMessenger) before main...
Optimism Etherscan
Etherscan-family block explorer for OP Mainnet and OP Sepolia with REST API access for contracts, transactions, and addresses.
Optimism Blockscout
Open-source Blockscout block explorer for OP Mainnet with REST and GraphQL APIs.
Optimism JSON-RPC API
Standard Ethereum JSON-RPC method invocation.
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Open Collections 3
Open, tool-agnostic API collections (OpenAPI-derived and Bruno).
API Collection
OPEN COLLECTIONOP Mainnet JSON-RPC API
OPEN COLLECTIONOP Mainnet JSON-RPC
OPEN COLLECTIONGraphQL 1
GraphQL schemas published by this provider.
Optimism GraphQL API
GRAPHQLPricing Plans 1
Published pricing tiers and plan structures.
Rate Limits 1
Documented rate limits and quota policies.
Optimism Rate Limits
RATE LIMITSFinOps 1
Cost, billing, and metering signals for API financial operations.
Optimism Finops
FINOPSEvent Specifications 1
AsyncAPI definitions for this provider's event-driven and streaming APIs.
Optimism (OP Stack) WebSocket JSON-RPC API
AsyncAPI 2.6 description of the WebSocket JSON-RPC subscription surface exposed by op-geth — the OP Stack execution client used by OP Mainnet (chain ID 10) and OP Sepolia (chain...
ASYNCAPISpectral Rules 1
Spectral governance rulesets for linting and validating these APIs.
Optimism API Rules
SPECTRALSecurity Posture 1
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Agentic Access 1
Recommended x-agentic-access execution contracts for AI agents.
Resources
Get Started 1
Portal, sign-up, and the first successful call
Documentation 1
Reference material describing how the API behaves
Agent Surfaces 2
MCP servers, agent skills, and machine-readable catalogs
Build 1
SDKs, sample code, and the tooling you integrate with
Access & Security 1
Authentication, authorization, and security posture
Operate 2
Status, limits, changes, and where to get help
Commercial 1
Pricing, plans, and the legal terms of use
Company 3
The organization behind the API
Other 2
Properties that don't map to a standard resource type