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Langfuse

Langfuse is an open-source LLM engineering platform offering tracing, evaluations, prompt management, datasets, and metrics. The Langfuse API supports both self-hosted and multi-region cloud deployments (US, EU, Japan, HIPAA-compliant US) and integrates with LangChain, LlamaIndex, OpenTelemetry, and any LLM stack.

agent ready

Limited machine-readable signal and partial portal coverage — documentation a human can read, but little a machine or agent can consume without scraping.

Kin Score

API Evangelist profiles Langfuse the way a machine reads it — 37 machine-readable artifacts across 28 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 — Langfuse scores 43.5/100 (thin), with a separate agent-readiness read of 48/100 (agent ready). 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 — 43.5/100 · thin
Contract Quality 11.9 / 25
Developer Ergonomics 5.2 / 20
Commercial Clarity 11.6 / 20
Operational Transparency 4.8 / 13
Governance 0.0 / 12
Discoverability 10.0 / 10
Agent readiness — 48/100 · agent ready
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 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

How we profile Langfuse

Each block below is one kind of artifact we hold for Langfuse. 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 28

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.

Langfuse AnnotationQueues API

The AnnotationQueues API from Langfuse — 5 operation(s) for annotationqueues.

Langfuse BlobStorageIntegrations API

The BlobStorageIntegrations API from Langfuse — 2 operation(s) for blobstorageintegrations.

Langfuse Comments API

The Comments API from Langfuse — 2 operation(s) for comments.

Langfuse DatasetItems API

The DatasetItems API from Langfuse — 2 operation(s) for datasetitems.

Langfuse DatasetRunItems API

The DatasetRunItems API from Langfuse — 1 operation(s) for datasetrunitems.

Langfuse Datasets API

The Datasets API from Langfuse — 4 operation(s) for datasets.

Langfuse Health API

The Health API from Langfuse — 1 operation(s) for health.

Langfuse Ingestion API

The Ingestion API from Langfuse — 1 operation(s) for ingestion.

Langfuse LegacyMetricsV1 API

The LegacyMetricsV1 API from Langfuse — 1 operation(s) for legacymetricsv1.

Langfuse LegacyObservationsV1 API

The LegacyObservationsV1 API from Langfuse — 2 operation(s) for legacyobservationsv1.

Langfuse LegacyScoreV1 API

The LegacyScoreV1 API from Langfuse — 2 operation(s) for legacyscorev1.

Langfuse LlmConnections API

The LlmConnections API from Langfuse — 2 operation(s) for llmconnections.

Langfuse Media API

The Media API from Langfuse — 2 operation(s) for media.

Langfuse Metrics API

The Metrics API from Langfuse — 1 operation(s) for metrics.

Langfuse Models API

The Models API from Langfuse — 2 operation(s) for models.

Langfuse Observations API

The Observations API from Langfuse — 1 operation(s) for observations.

Langfuse Opentelemetry API

The Opentelemetry API from Langfuse — 1 operation(s) for opentelemetry.

Langfuse Organizations API

The Organizations API from Langfuse — 4 operation(s) for organizations.

Langfuse Projects API

The Projects API from Langfuse — 4 operation(s) for projects.

Langfuse Prompts API

The Prompts API from Langfuse — 2 operation(s) for prompts.

Langfuse PromptVersion API

The PromptVersion API from Langfuse — 1 operation(s) for promptversion.

Langfuse Scim API

The Scim API from Langfuse — 5 operation(s) for scim.

Langfuse ScoreConfigs API

The ScoreConfigs API from Langfuse — 2 operation(s) for scoreconfigs.

Langfuse Scores API

The Scores API from Langfuse — 2 operation(s) for scores.

Langfuse Sessions API

The Sessions API from Langfuse — 2 operation(s) for sessions.

Langfuse Trace API

The Trace API from Langfuse — 2 operation(s) for trace.

Langfuse UnstableEvaluationRules API

The UnstableEvaluationRules API from Langfuse — 2 operation(s) for unstableevaluationrules.

Langfuse UnstableEvaluators API

The UnstableEvaluators API from Langfuse — 2 operation(s) for unstableevaluators.

Scroll within the panel for all 28 ·

Open Collections 1

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).

langfuse

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.

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.

Langfuse Rate Limits

4 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.

Security Posture 4

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.

Langfuse Authentication

http · 1 scheme

SECURITY

Langfuse Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Langfuse Vulnerability Disclosure

disclosure policy published

SECURITY

Langfuse Trust Center

SOC 2, ISO 27001, HIPAA, GDPR

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.

Langfuse Agentic Access

96 operations · 46 acting

96 operations · 46 acting

AGENTIC

Resources

Every other property we hold for Langfuse — 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.

Documentation 2

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

Operate 1

Status, limits, changes, and where to get help

Commercial 3

Pricing, plans, and the legal terms of use

Company 2

The organization behind the API

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