Introduction

Tape out a circuit, and its container is your API. TapeAPI is the service and communication layer of the TapeOut ecosystem on BNB Chain: DeWEB is websites, TapeSend is messaging, and TapeAPI is services.

An API today is a URL plus an account plus trust. TapeAPI replaces the account with an on-chain identity and the trust with a signature anyone can check:

• The service is a circuit. Whoever holds the circuit NFT owns the service. Transfer the NFT and the service moves with it.
• Every answer is signed and bound to your request. A client checks the signature against a key the circuit's holder authorised on chain. A tampered, replayed or unsigned answer is an error, never a result.
• No sign-up, no API keys. Free methods are just called. Paid methods take off-chain vouchers that settle on chain in batches. There is no mandatory protocol fee: a default 1% maintenance contribution comes out of the provider's share, and any provider can set it to 0. No call is charged today; the escrow is not deployed yet.
• Containers can talk privately. End-to-end encrypted channels and groups between containers, carried by relays or by the chain itself.

#How it works

1. Identity. A provider tapes out a circuit on TapeOut. The circuit's container (an ERC-6551 account) is the service's address.
2. Manifest. The provider writes .well-known/tapeapi.json into the container's site: endpoints, methods, prices, the signing key, and the holder's EIP-712 delegation of that key.
3. Resolve. A client reads the manifest from the chain through several RPC nodes that must agree, checks its hash, and checks the delegation against the circuit's current holder.
4. Call. The client sends a request; the service answers with an envelope signed by the delegated key and bound to that request. The SDK returns the result only after checking it.

#Choose your path

#Status

The latest release is 3.0.0 (2026-11-06). TapeAPI follows semantic versioning: code written against the 3.0 docs keeps working in every 3.x release (as code written against the 2.0 docs does in every 2.x release), and breaking changes come only in a new major version. By default 2.0 resolves a service as TapeOut's official TAPs say (TAP-10, TAP-11 §2), with one known exception; 1.x receives security fixes for 6 months after 2.0.0 (Upgrading to 2.0; what 1.0 promises). The free tier runs on TapeOut's deployed contracts. Our own contracts have no third-party audit; the paid-call escrow is not deployed yet. TAPI-20 to TAPI-27 are TapeAPI's own specs, not TAPs: TAPs are numbered by the editors of TapeOutProtocol/TAPs, where seven of our drafts were merged as Drafts (TAP-11, TAP-13, TAP-14, TAP-15, TAP-16, TAP-17, TAP-18; merging is not adoption) and seven more are submitted (in review), without a number.

#On-chain addresses

BNB Smart Chain, chainId 56.

#Public services

Free TapeAPI services run by the project, each under its own circuit on processor 1013 (0xe02c26c7432A7121168AA9B610DE24eCf9a1a414). They are services, not contracts; see Public API.

The public API's methods are also MCP tools at https://api.tapeapi.fun/mcp, for Claude, Cursor and any MCP client. Every result is signed and carries a receipt anyone can verify; see MCP.

#Specifications

The protocol is written down as TapeAPI's own specs (TAPI), in English and Chinese (English authoritative), under CC0. They are not TAPs. We submitted fourteen TAP drafts for parts of them to TapeOutProtocol/TAPs (eight on 2026-09-30 and 2026-10-01, two on the container-agent formats on 2026-10-04 and 2026-10-05, two on 2026-10-08, two on 2026-10-13): seven are merged as Drafts (merging is not adoption): the service identity and manifest as TAP-11 (#8, 2026-10-01), signed responses as TAP-13 (#10, 2026-10-04), and, on 2026-11-03, private channels as TAP-14 (#12), MCP tools as service methods as TAP-15 (#16), attested reads as TAP-16 (#18), AI usage receipts as TAP-17 (#26) and container agent mandates and task messages, phase 0, as TAP-18 (#47); seven are submitted (in review): #20, #28, #49, #52, #54, #59 and #60 (the last one now a draft PR). One more draft, an Information draft, #61 (a privacy map), is submitted (in review). TAPI-20 to TAPI-27 (with version 2 of TAPI-26 and TAPI-27) remain the basis of the compatibility promise.

Source code, examples and the conformance suite are on GitHub.

#Credits

The idea of a service layer for TapeOut came from @Theairresearch. From 2026-10-05, 10% of TapeAPI's revenue each quarter, after the direct cash costs paid to third parties, goes to them permanently (definition in BUSINESS.md).