Taxi - Describe How Your APIs and Data Relate

Taxi is an open-source language (Apache 2.0) for describing APIs, data models, and how data relates across an entire ecosystem. TaxiQL is a declarative query language that lets consumers define the data they want while Taxi handles orchestration across REST APIs, databases, Kafka topics, gRPC services, and S3 buckets. Taxi eliminates manual integration code by using semantic type annotations to automatically discover data paths and adapt to evolving API schemas.

Taxi - Describe How Your APIs and Data Relate publishes 5 APIs on the APIs.io network, including Conversion API, Queries API, Schemas API, and 2 more. Tagged areas include API Description, Data Integration, Open-Source, Query Language, and Schema.

The Taxi - Describe How Your APIs and Data Relate catalog on APIs.io includes 1 JSON-LD context and 2 Spectral governance rulesets.

Taxi - Describe How Your APIs and Data Relate’s developer surface includes documentation and 12 more developer resources.

🌐 Visit website 📡 Source on GitHub

30.2/100 thin ▬ flat Agent 17/100 agent aware Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessFreemium

1 APIs

API Description Data Integration Open-Source Query Language Schema Semantic

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 30.2/100 · thin

Contract Quality 12.4 / 23

Developer Ergonomics 2.6 / 18

Access Clarity 2.8 / 18

Operational Transparency 1.5 / 12

Contract Governance 3.1 / 11

Discoverability 5.3 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 17/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 0 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

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/taxi: 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 8

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

TaxiQL Query API

TaxiQL is a declarative query language for federated data retrieval across multiple APIs and data sources. Queries specify the desired data structure using semantic types and Ta...

Orbital Platform

Orbital is the companion data platform for Taxi that hosts TaxiQL queries, provides a schema registry, and executes federated data integrations across APIs, databases, and strea...

Taxi Playground

Interactive web-based editor for writing Taxi schemas and TaxiQL queries with live diagram generation and query execution preview.

Taxi - Describe How Your APIs and Data Relate Conversion API

Convert existing specs to Taxi format

Taxi - Describe How Your APIs and Data Relate Queries API

TaxiQL query execution

Taxi - Describe How Your APIs and Data Relate Schemas API

Taxi schema management and compilation

Taxi - Describe How Your APIs and Data Relate Services API

Service registry operations

Taxi - Describe How Your APIs and Data Relate Types API

Type registry and discovery

Scroll for all 8

Open Collections 7

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

API Collection

OPEN COLLECTION

Taxi Language Conversion API

OPEN COLLECTION

Taxi Language API

OPEN COLLECTION

Taxi Language Conversion Queries API

OPEN COLLECTION

Taxi Language Conversion Schemas API

OPEN COLLECTION

Taxi Language Conversion Services API

OPEN COLLECTION

Taxi Language Conversion Types API

OPEN COLLECTION

Scroll for all 7

Pricing Plans 1

Published pricing tiers and plan structures.

Taxi Plans Pricing

7 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Taxi Rate Limits

5 limits

RATE LIMITS

FinOps 1

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

Taxi Finops

FINOPS

Semantic Vocabularies 1

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

Taxi Context

24 classes · 0 properties

JSON-LD

Spectral Rules 2

Spectral governance rulesets for linting and validating these APIs.

Taxi - Describe How Your APIs and Data Relate API Rules

6 rules · 5 warnings 1 info

SPECTRAL

Taxi - Describe How Your APIs and Data Relate API Rules

16 rules · 3 errors 13 warnings

SPECTRAL

JSON Schema 1

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

Taxi Schema Definition

6 properties

JSON SCHEMA

JSON Structure 1

JSON Structure definitions describing this provider's data shapes.

Taxi Schema Structure

0 properties

JSON STRUCTURE

Examples 2

Example request and response payloads for these APIs.

Taxi Compile Schema Example

2 fields

EXAMPLE

Taxi Execute Query Example

2 fields

EXAMPLE

Security Posture 1

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

Taxi Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Agentic Access 1

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

Taxi Agentic Access

11 operations · 4 acting

AGENTIC

Resources

Documentation 3

Reference material describing how the API behaves

Documentation

Documentation

OpenAPI

OpenAPI

JSONSchema

JSONSchema

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Design & Contract 3

Pagination, idempotency, versioning, errors, and events

JSONStructure

JSONStructure

JSONLD

JSONLD

Vocabulary

Vocabulary

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrg

GitHubOrg

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Operate 1

Status, limits, changes, and where to get help

Slack

Slack

Company 2

The organization behind the API

LinkedIn

Website

Website

Other 1

Properties that don't map to a standard resource type

Playground

Playground

Source (apis.yml)

aid: taxi
name: Taxi - Describe How Your APIs and Data Relate
description: Taxi is an open-source language (Apache 2.0) for describing APIs, data models, and how data relates across an
  entire ecosystem. TaxiQL is a declarative query language that lets consumers define the data they want while Taxi handles
  orchestration across REST APIs, databases, Kafka topics, gRPC services, and S3 buckets. Taxi eliminates manual integration
  code by using semantic type annotations to automatically discover data paths and adapt to evolving API schemas.
type: Index
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
position: Consuming
access: 3rd-Party
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/taxi.png
tags:
- API Description
- Data Integration
- Open-Source
- Query Language
- Schema
- Semantic
tags_raw:
- API Description
- Data Integration
- Open Source
- Query Language
- Schema
- Semantic
created: '2026-01-05'
modified: '2026-05-19'
url: https://raw.githubusercontent.com/api-evangelist/taxi/refs/heads/main/apis.yml
specificationVersion: '0.23'
apis:
- aid: taxi-describe-how-your-apis-and-data-relate:taxiql-query-api
  name: TaxiQL Query API
  description: TaxiQL is a declarative query language for federated data retrieval across multiple APIs and data sources.
    Queries specify the desired data structure using semantic types and Taxi automatically discovers the data paths, calls
    APIs, and assembles results.
  humanURL: https://docs.taxilang.org/language-reference/querying-with-taxiql/
  tags:
  - Data Query
  - Federated Query
  - Open-Source
  - Query Language
  tags_raw:
  - Data Query
  - Federated Query
  - Open Source
  - Query Language
  properties:
  - type: Documentation
    url: https://docs.taxilang.org/language-reference/querying-with-taxiql/
  - type: GitHub
    url: https://github.com/taxilang/taxilang
- aid: taxi-describe-how-your-apis-and-data-relate:orbital-platform
  name: Orbital Platform
  description: Orbital is the companion data platform for Taxi that hosts TaxiQL queries, provides a schema registry, and
    executes federated data integrations across APIs, databases, and streams using Taxi annotations.
  humanURL: https://orbitalhq.com
  tags:
  - Data Platform
  - Federated Query
  - Integration
  - Schema Registry
  properties:
  - type: Documentation
    url: https://orbitalhq.com
- aid: taxi-describe-how-your-apis-and-data-relate:taxi-playground
  name: Taxi Playground
  description: Interactive web-based editor for writing Taxi schemas and TaxiQL queries with live diagram generation and query
    execution preview.
  humanURL: https://playground.taxilang.org
  tags:
  - Developer Tools
  - Playground
  - Schema Editor
  properties:
  - type: Documentation
    url: https://playground.taxilang.org
- aid: taxi:taxi-conversion-api
  name: Taxi - Describe How Your APIs and Data Relate Conversion API
  description: Convert existing specs to Taxi format
  humanURL: https://taxilang.org/
  tags:
  - Conversion
  properties:
  - type: OpenAPI
    url: openapi/taxi-conversion-api-openapi.yml
  - type: Documentation
    url: https://docs.taxilang.org/
  - type: GitHub
    url: https://github.com/taxilang/taxilang
- aid: taxi:taxi-queries-api
  name: Taxi - Describe How Your APIs and Data Relate Queries API
  description: TaxiQL query execution
  humanURL: https://taxilang.org/
  tags:
  - Query
  tags_raw:
  - Queries
  properties:
  - type: OpenAPI
    url: openapi/taxi-queries-api-openapi.yml
  - type: Documentation
    url: https://docs.taxilang.org/
  - type: GitHub
    url: https://github.com/taxilang/taxilang
- aid: taxi:taxi-schemas-api
  name: Taxi - Describe How Your APIs and Data Relate Schemas API
  description: Taxi schema management and compilation
  humanURL: https://taxilang.org/
  tags:
  - Schemas
  properties:
  - type: OpenAPI
    url: openapi/taxi-schemas-api-openapi.yml
  - type: Documentation
    url: https://docs.taxilang.org/
  - type: GitHub
    url: https://github.com/taxilang/taxilang
- aid: taxi:taxi-services-api
  name: Taxi - Describe How Your APIs and Data Relate Services API
  description: Service registry operations
  humanURL: https://taxilang.org/
  tags:
  - Services
  properties:
  - type: OpenAPI
    url: openapi/taxi-services-api-openapi.yml
  - type: Documentation
    url: https://docs.taxilang.org/
  - type: GitHub
    url: https://github.com/taxilang/taxilang
- aid: taxi:taxi-types-api
  name: Taxi - Describe How Your APIs and Data Relate Types API
  description: Type registry and discovery
  humanURL: https://taxilang.org/
  tags:
  - Types
  properties:
  - type: OpenAPI
    url: openapi/taxi-types-api-openapi.yml
  - type: Documentation
    url: https://docs.taxilang.org/
  - type: GitHub
    url: https://github.com/taxilang/taxilang
common:
- type: AgenticAccess
  url: agentic-access/taxi-agentic-access.yml
- type: DomainSecurity
  url: security/taxi-domain-security.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/taxi
- type: Website
  url: https://taxilang.org/
- type: Documentation
  url: https://docs.taxilang.org/
- type: GitHubOrg
  url: https://github.com/taxilang
- type: Playground
  url: https://playground.taxilang.org
- type: Slack
  url: https://join.slack.com/t/taxi-lang/shared_invite
- type: OpenAPI
  url: openapi/_original/taxi-language-openapi.yml
- type: JSONSchema
  url: json-schema/taxi-schema-definition-schema.json
- type: JSONStructure
  url: json-structure/taxi-schema-structure.json
- type: JSONLD
  url: json-ld/taxi-context.jsonld
- type: Vocabulary
  url: vocabulary/taxi-vocabulary.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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