Vellum AI
Vellum AI is an LLM development platform that helps product and engineering teams build, evaluate, deploy, and monitor LLM-powered applications. The platform centers on prompt engineering, a visual Workflows builder for agentic and multi-step pipelines, evaluation suites with dataset management, retrieval-augmented generation, and production observability with logs, traces, and metrics. Target customers are AI product teams at startups and enterprises that need version control, collaboration, and vendor-neutral access across OpenAI, Anthropic, Google, Mistral, and open models. Vellum exposes a REST API plus Python and TypeScript SDKs, runs in cloud and self-hosted deployments, and offers tiered pricing for Pro/Business/Enterprise. Note: as of 2026 the vellum.ai marketing surface has been refocused on a personal AI assistant product; the developer platform documented here remains the LLM application stack.
Limited machine-readable signal and partial portal coverage — documentation a human can read, but little a machine or agent can consume without scraping.
API Evangelist profiles Vellum AI the way a machine reads it — 23 machine-readable artifacts across 16 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 — Vellum AI scores 44.9/100 (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
How this is scored →scored 2026-07-27 · rubric v0.5
How we profile Vellum AI
Each block below is one kind of artifact we hold for Vellum AI. 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 16
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.
Vellum LLM Platform API
The Vellum REST API exposes prompts, workflows, evaluations, datasets, document indexes, deployments, and execution endpoints so developers can run versioned LLM pipelines from ...
Vellum AI Default API
The Default API from Vellum AI — 8 operation(s) for default.
Vellum AI subpackage_deployments API
The subpackage_deployments API from Vellum AI — 7 operation(s) for subpackage_deployments.
Vellum AI subpackage_documentIndexes API
The subpackage_documentIndexes API from Vellum AI — 3 operation(s) for subpackage_documentindexes.
Vellum AI subpackage_documents API
The subpackage_documents API from Vellum AI — 3 operation(s) for subpackage_documents.
Vellum AI subpackage_events API
The subpackage_events API from Vellum AI — 1 operation(s) for subpackage_events.
Vellum AI subpackage_folderEntities API
The subpackage_folderEntities API from Vellum AI — 2 operation(s) for subpackage_folderentities.
Vellum AI subpackage_sandboxes API
The subpackage_sandboxes API from Vellum AI — 3 operation(s) for subpackage_sandboxes.
Vellum AI subpackage_testSuiteRuns API
The subpackage_testSuiteRuns API from Vellum AI — 3 operation(s) for subpackage_testsuiteruns.
Vellum AI subpackage_testSuites API
The subpackage_testSuites API from Vellum AI — 3 operation(s) for subpackage_testsuites.
Vellum AI subpackage_uploadedFiles API
The subpackage_uploadedFiles API from Vellum AI — 1 operation(s) for subpackage_uploadedfiles.
Vellum AI subpackage_workflowDeployments API
The subpackage_workflowDeployments API from Vellum AI — 10 operation(s) for subpackage_workflowdeployments.
Vellum AI subpackage_workflowExecutions API
The subpackage_workflowExecutions API from Vellum AI — 1 operation(s) for subpackage_workflowexecutions.
Vellum AI subpackage_workflows API
The subpackage_workflows API from Vellum AI — 1 operation(s) for subpackage_workflows.
Vellum AI subpackage_workflowSandboxes API
The subpackage_workflowSandboxes API from Vellum AI — 1 operation(s) for subpackage_workflowsandboxes.
Vellum AI subpackage_workspaceSecrets API
The subpackage_workspaceSecrets API from Vellum AI — 1 operation(s) for subpackage_workspacesecrets.
Scroll within the panel for all 16 ·
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).
Client SDK
OPEN COLLECTIONPricing 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.
Vellum Plans Pricing
PLANSRate 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.
Vellum Rate Limits
RATE LIMITSFinOps 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.
Vellum Finops
FINOPSSecurity 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.
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.
Resources
Every other property we hold for Vellum AI — 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.
Get Started 2
Portal, sign-up, and the first successful call
Documentation 1
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
Access & Security 2
Authentication, authorization, and security posture
Commercial 3
Pricing, plans, and the legal terms of use
Company 4
The organization behind the API
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