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Tensor

Tensor is the Solana-native NFT marketplace and trading protocol founded by Tensor HQ and now stewarded by the Tensor Foundation. The platform exposes a public read REST API, a transaction-construction (TX) API that returns unsigned Solana transactions for list / buy / bid / pool flows, and a WebSocket subscription stream for realtime marketplace events. Five open-source Anchor programs — Marketplace, AMM v2, Whitelist, Escrow, and Fees — back the protocol and ship as `@tensor-foundation/*` JavaScript SDKs and `tensor-*` Rust crates. Tensor supports legacy NFTs, programmable NFTs (pNFT), and Bubblegum compressed NFTs (cNFT), and serves as the execution layer behind aggregators, wallets, sales bots, and AMM bonding-curve liquidity providers across the Solana ecosystem. Governance and ecosystem grants flow through the TNSR token and the Tensor DAO on Realms.

agent native

Real signal across most facets with visible, nameable gaps — the contract exists but is thin, or the portal is good while governance and commercial terms are absent.

Kin Score

API Evangelist profiles Tensor the way a machine reads it — 47 machine-readable artifacts across 9 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Tensor scores 54.7/100 (developing), with a separate agent-readiness read of 61/100 (agent native). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 54.7/100 · developing
Contract Quality 18.8 / 25
Developer Ergonomics 11.3 / 20
Commercial Clarity 5.8 / 20
Operational Transparency 4.8 / 13
Governance 7.3 / 12
Discoverability 10.0 / 10
Regulatory · Securities & Market Data 5.6 / 15
Agent readiness — 61/100 · agent native
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 7 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 6 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3

How we profile Tensor

Each block below is one kind of artifact we hold for Tensor. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 9

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

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

Tensor WebSocket API

Subscription-based realtime stream of Tensor marketplace events. Channels include `newTransaction` (every confirmed marketplace action), `ammOrderUpdate` / `ammOrderUpdateAll` (...

Tensor Bids API

The Bids API from Tensor — 8 operation(s) for bids.

Tensor Collections API

The Collections API from Tensor — 5 operation(s) for collections.

Tensor Escrow API

The Escrow API from Tensor — 2 operation(s) for escrow.

Tensor Listings API

The Listings API from Tensor — 6 operation(s) for listings.

Tensor NFTs API

The NFTs API from Tensor — 3 operation(s) for nfts.

Tensor Pools API

The Pools API from Tensor — 7 operation(s) for pools.

Tensor User API

The User API from Tensor — 10 operation(s) for user.

Tensor Utility API

The Utility API from Tensor — 6 operation(s) for utility.

Scroll within the panel for all 9 ·

Open Collections 2

Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Tensor API

OPEN COLLECTION

Pricing Plans 1

Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.

Published pricing tiers and plan structures.

Tensor Plans Pricing

2 plans

PLANS

Rate Limits 1

Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.

Documented rate limits and quota policies.

Tensor Rate Limits

3 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.

Cost, billing, and metering signals for API financial operations.

Features 16

The notable capabilities this provider advertises, captured as structured features so they can be searched and compared instead of read one landing page at a time.

Notable capabilities this provider offers.

Solana's leading NFT marketplace covering 30,000+ collections with deep liquidity
Read API (REST) covering collections, listings, bids, pools, mints, user portfolios, transaction history, and royalty enforcement
Transaction (TX) API that returns unsigned base64 Solana transactions for list / delist / buy / bid / pool ops — clients sign locally
WebSocket subscriptions for `newTransaction`, `ammOrderUpdate`, `tcompBidUpdate`, with ping/unsubscribe control frames
Supports legacy NFTs, programmable NFTs (pNFT), and Bubblegum compressed NFTs (cNFT)
TensorSwap AMM v2 with bonding curves (linear, exponential) and shared escrow for capital-efficient market making
Collection-wide bids, single-NFT bids, and trait-attribute bids
Creator Portal — collection claim/verification, launchpad, and royalty configuration
YOLO Buy aggregator and floor-purchase recipes
On-chain programs are open-source (Apache-2.0) Anchor programs published as IDLs, npm packages, and Rust crates
Five official programs — Marketplace, AMM v2, Whitelist, Escrow, Fees — each shipped as `@tensor-foundation/*` npm and `tensor-*` crates.io packages
Authentication via `x-tensor-api-key` header issued through dev.tensor.trade after Airtable application
smart-rpc transport, Unified Wallet Kit, Next.js / Discord / Telegram starter templates published on GitHub
TNSR token (mint `TNSRxcUxoT9xBG3de7PiJyTDYu7kskLqcpddxnEJAS6`) — 1B supply, governance via Realms DAO at app.realms.today/dao/TNSR
Tensor Foundation Grants program for ecosystem builders
Multiple third-party audits of Anchor programs published at docs.tensor.foundation/audits

Scroll within the panel for all 16 ·

Event Specifications 1

Not every API is request/response. AsyncAPI describes the event-driven and streaming side — the webhooks and channels — so the asynchronous half of the interface is documented the same way the synchronous half is.

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Tensor WebSocket API

Realtime subscription stream for the Tensor Solana NFT marketplace. Clients open a single WebSocket connection authenticated with `x-tensor-api-key`, then send JSON subscribe/un...

ASYNCAPI

Semantic Vocabularies 1

JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.

JSON-LD contexts and semantic vocabularies used across these APIs.

Tensor Context

47 classes · 3 properties

JSON-LD

Spectral Rules 3

Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.

Tensor API Rules

10 rules · 1 errors · 8 warnings

SPECTRAL

Tensor API Rules

5 rules · 3 warnings

SPECTRAL

Tensor API Rules

6 rules · 2 errors · 4 warnings

SPECTRAL

JSON Schema 5

Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.

Standalone JSON Schema definitions for this provider's data models.

Tensor Bid

11 properties

JSON SCHEMA

Tensor Collection

18 properties

JSON SCHEMA

Tensor Listing

10 properties

JSON SCHEMA

Tensor Mint

10 properties

JSON SCHEMA

Tensor AMM Pool

12 properties

JSON SCHEMA

Examples 4

Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.

Example request and response payloads for these APIs.

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

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

Tensor Authentication

apiKey · 1 scheme

SECURITY

Tensor Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.

Recommended x-agentic-access execution contracts for AI agents.

Tensor Agentic Access

47 operations · 2 acting

47 operations · 2 acting

AGENTIC

Resources

Every other property we hold for Tensor — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Access & Security 2

Authentication, authorization, and security posture

Operate 2

Status, limits, changes, and where to get help

Commercial 2

Pricing, plans, and the legal terms of use

Company 1

The organization behind the API

Other 2

Properties that don't map to a standard resource type

← All providers · Data indexed from github.com/api-evangelist/tensor · machine-readable index on apis.io