# LangSmith

**Canonical:** https://apis.io/providers/langsmith/  
**Website:** https://smith.langchain.com/  
**APIs profiled:** 73

LangSmith is the observability, debugging, and evaluation platform for LLM applications, built by LangChain. The LangSmith API exposes tracing, dataset management, evaluation, prompt-hub, and Fleet agent functionality for AI engineering teams.

## Kin Score — 31.0 / 100 (thin)

Scored 2026-08-25 under rubric 0.14.0. Trend: flat (+0.0 from 31.0).

| Facet | Score |
|---|---|
| Discoverability | 68.5 |
| Contract Quality | 52.3 |
| Governance | 0.0 |
| Contract Governance | 0.0 |
| Operational Transparency | 7.9 |
| Developer Ergonomics | 23.8 |
| Commercial Clarity | 26.3 |
| Access Clarity | 26.3 |

## Agent readiness — 28.1 (agent-aware)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | no |
| MCP Server | no |
| Auth Clarity | bearer |
| Idempotency | no |
| Error Semantics | verified |
| OpenAPI Examples | partial |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | no |
| Delegated Identity | no |
| Protected Resource Metadata | no |
| Dynamic Client Registration | no |
| Agentic Commerce | no |

## Access

Freemium · Self-serve signup — onboarding: self-serve, pricing: freemium, trial: no (confidence: high).

## APIs (73)

- **LangSmith access_policies API** — The access_policies API from LangSmith — 3 operation(s) for access_policies.
- **LangSmith ace API** — The ace API from LangSmith — 1 operation(s) for ace.
- **LangSmith agents API** — The agents API from LangSmith — 2 operation(s) for agents.
- **LangSmith alert_rules API** — The alert_rules API from LangSmith — 3 operation(s) for alert_rules.
- **LangSmith annotation-queues API** — The annotation-queues API from LangSmith — 17 operation(s) for annotation-queues.
- **LangSmith api-key API** — The api-key API from LangSmith — 4 operation(s) for api-key.
- **LangSmith audit-logs API** — The audit-logs API from LangSmith — 1 operation(s) for audit-logs.
- **LangSmith auth API** — The auth API from LangSmith — 7 operation(s) for auth.
- **LangSmith aws_marketplace API** — The aws_marketplace API from LangSmith — 1 operation(s) for aws_marketplace.
- **LangSmith backfills API** — The backfills API from LangSmith — 1 operation(s) for backfills.
- **LangSmith beacon API** — The beacon API from LangSmith — 1 operation(s) for beacon.
- **LangSmith bulk-exports API** — The bulk-exports API from LangSmith — 7 operation(s) for bulk-exports.
- **LangSmith charts API** — The charts API from LangSmith — 13 operation(s) for charts.
- **LangSmith comments API** — The comments API from LangSmith — 3 operation(s) for comments.
- **LangSmith commits API** — The commits API from LangSmith — 2 operation(s) for commits.
- **LangSmith data_planes API** — The data_planes API from LangSmith — 1 operation(s) for data_planes.
- **LangSmith datasets API** — The datasets API from LangSmith — 28 operation(s) for datasets.
- **LangSmith directories API** — The directories API from LangSmith — 2 operation(s) for directories.
- **LangSmith evaluators API** — The evaluators API from LangSmith — 2 operation(s) for evaluators.
- **LangSmith examples API** — The examples API from LangSmith — 9 operation(s) for examples.
- **LangSmith experiment-view-overrides API** — The experiment-view-overrides API from LangSmith — 2 operation(s) for experiment-view-overrides.
- **LangSmith experiments API** — The experiments API from LangSmith — 1 operation(s) for experiments.
- **LangSmith features API** — The features API from LangSmith — 4 operation(s) for features.
- **LangSmith feedback API** — The feedback API from LangSmith — 7 operation(s) for feedback.
- **LangSmith feedback-configs API** — The feedback-configs API from LangSmith — 1 operation(s) for feedback-configs.
- **LangSmith fleet auth API** — The fleet auth API from LangSmith — 10 operation(s) for fleet auth.
- **LangSmith fleet github-app API** — The fleet github-app API from LangSmith — 9 operation(s) for fleet github-app.
- **LangSmith fleet integrations API** — The fleet integrations API from LangSmith — 3 operation(s) for fleet integrations.
- **LangSmith fleet mcp API** — The fleet mcp API from LangSmith — 7 operation(s) for fleet mcp.
- **LangSmith fleet threads API** — The fleet threads API from LangSmith — 5 operation(s) for fleet threads.
- **LangSmith fleet usage API** — The fleet usage API from LangSmith — 4 operation(s) for fleet usage.
- **LangSmith fleet_webhooks API** — The fleet_webhooks API from LangSmith — 1 operation(s) for fleet_webhooks.
- **LangSmith gateway API** — The gateway API from LangSmith — 4 operation(s) for gateway.
- **LangSmith gateway-policies API** — The gateway-policies API from LangSmith — 2 operation(s) for gateway-policies.
- **LangSmith hub_environments API** — The hub_environments API from LangSmith — 2 operation(s) for hub_environments.
- **LangSmith info API** — The info API from LangSmith — 2 operation(s) for info.
- **LangSmith integrations API** — The integrations API from LangSmith — 1 operation(s) for integrations.
- **LangSmith likes API** — The likes API from LangSmith — 1 operation(s) for likes.
- **LangSmith mcp API** — The mcp API from LangSmith — 2 operation(s) for mcp.
- **LangSmith mcp_vendors API** — The mcp_vendors API from LangSmith — 6 operation(s) for mcp_vendors.
- …and 33 more, listed in full on the page.

## Agentic access (1)

- **Langsmith Agentic Access** — 556 operations · 343 acting · 14 human-in-the-loop

## Security (2)

- **Langsmith Authentication** — apiKey/http · 4 schemes
- **Langsmith Domain Security** — TLSv1.3 · HSTS · DNSSEC · DMARC

## Plans (1)

- **Langsmith Plans Pricing**

## Tags

Artificial Intelligence, LLM, Observability, Evaluations, LangChain

---

Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/langsmith/). Scores are computed from the provider's own public artifacts under a published rubric.