Vellum alternatives
The highest-scoring alternative to Vellum is CrewAI at 79/100 on the AgentReady, against 88/100 for Vellum.
All scored in Agent Frameworks & Runtimes.
| Score | Alternative | Compare |
|---|---|---|
| 79 | CrewAI | Vellum vs CrewAI |
| 79 | PydanticAI | Vellum vs PydanticAI |
| 65 | Agno | Vellum vs Agno |
| 65 | Lmstudio | Vellum vs Lmstudio |
| 64 | Ramp | Vellum vs Ramp |
| 55 | Treblle | Vellum vs Treblle |
| 53 | AutoGen (AG2) | Vellum vs AutoGen (AG2) |
| 52 | LlamaIndex | - |
| 51 | Adobe | - |
| 48 | Camel Ai | - |
| 48 | Last9 | - |
| 42 | Electric Sql | - |
| 42 | Mastra | - |
| 38 | Marqo | - |
| 34 | LangGraph | - |
| 34 | Pulsemcp | - |
| n/a | Venice | - |
What CrewAI does that Vellum does not
CrewAI passes authentication documented, and Vellum fails it. That is the whole of the gap between the two scores, so if none of those matter to your agent the ranking above overstates the difference.
Why people look for an alternative
Vellum fails authentication documented, limits / constraints documented, idempotency support, rate-limit behavior predictable, agent compatibility verified. Each one is a place an unattended run stops, which is usually what sends someone looking in the first place.
Where Vellum loses the points
| Pillar | Vellum | What it measures |
|---|---|---|
| Discover | 100 | Can an agent find it at all: sitemap, robots, structured data. |
| Understand | 85 | Is there a spec, an llms.txt, a machine-readable description. |
| Adopt | 100 | Signup, keys, SDKs, and whether a human has to be involved. |
| Operate | 67 | Rate-limit headers, errors, status, and behaviour under load. |
Vellum is weakest on operate at 67/100. Missing rate-limit headers mean an agent finds the limit by hitting it. If that is the part your agent depends on, take the ranking above seriously; if it is not, Vellum may still be the right pick.
What an agent runs into with Vellum
These are the findings from the last audit on 2026-08-23. Each one is a place unattended software stops, which is the practical reason to look at the list above.
- Return X-RateLimit / Retry-After headers so agents pace themselves.
- Support an Idempotency-Key so retries are safe.
What this category actually supports
Across the 18 products scored in Agent Frameworks & Runtimes, build an agent is offered by 61%, orchestrate agents is offered by 22%, agent memory is offered by 0%. Anything under half is a gap you should expect to fill yourself whichever one you pick.
An agent can get this list directly: resolve("alternative to Vellum") over the MCP server, or GET /v1/categories/agent-frameworks.