Registry › Compare › Haystack vs PydanticAI

Haystack vs PydanticAI

Haystack leads on trust: 96.4/100 (Grade A) against 89.3/100 (Grade A), a 7.1-point gap. Haystack leads on supply-chain integrity and transparency; PydanticAI leads on adoption and rests on broader evidence. Note: Haystack's evidence coverage is thinner (coverage B vs A) — its score rests on fewer independent signal types.

A Haystack 96.4

Open-source AI orchestration framework for building context-engineered, production-ready LLM applications. Design modular pipelines and agent workflows with explicit control over retrieval, routing, memory, and generation. Built for scalable agents, RAG, multimodal applications, semantic search…

deepset-ai/haystack · #1 overall · #1 Agent Frameworks · coverage B (3/5)

Choose Haystack if supply-chain integrity and transparency matter most.

  • +3.5Safety / Integrity: OSSF Scorecard 9.3 against 6.5
  • +2.4Transparency: OSSF Scorecard 9.3 against 6.5
A PydanticAI 89.3

How Python does AI. Agents, realtime voice, image generation, embeddings. Every model, every interface, typed end to end.

pydantic/pydantic-ai · #25 overall · #8 Agent Frameworks · coverage A (4/5)

Choose PydanticAI if adoption matters most.

  • +1.0Adoption: 1.3M weekly downloads against 152k
  • A vs BEvidence coverage: 4 of 5 independent signal types, against 3

Where they differ

24.1
Safety / IntegrityHaystack +3.5
20.6
16.4
TransparencyHaystack +2.4
14.0
19.9
MaintenancePydanticAI +0.1
20.0
17.5
AdoptionPydanticAI +1.0
18.5
+0.5
Runtime calibrationHaystack +2.3
-1.8

1 dimension identical: Identity 18.0 · Full evidence table

An independent, evidence-based trust comparison of Haystack and PydanticAI, two Agent Frameworks projects in the HVTracker registry. Scores come from public, checkable signals — supply-chain provenance, OSSF Scorecard, maintenance, and adoption — not popularity.

Full evidence

Signal Haystackdeepset-ai/haystack PydanticAIpydantic/pydantic-ai
HVTrust score 96.4 89.3
Evidence grade A A
Coverage grade B A
Overall rank #1 #25
Rank in Agent Frameworks #1 #8
GitHub stars 26.6k 20.4k
Last updated 1d ago today
Build provenance Yes Yes
OSSF Scorecard 9.3 / 10 6.5 / 10
License Apache-2.0 MIT
Downloads 152k/wk 1.3M/wk
Trust dimensions (points earned)
Safety / integrity / 25 24.1 20.6
Identity & provenance / 18 18.0 18.0
Transparency / 17 16.4 14.0
Maintenance / 20 19.9 20.0
Adoption / 20 17.5 18.5
Runtime capability surface (full matrix)
MCP server Declared Declared
External providers 1 — OpenAI 8 — Amazon Bedrock, Anthropic, Cohere, …
Requires API keys No No
Plugin surface plugins plugins
Provenance drift Match Match
Open in the live compare tool → Haystack profile PydanticAI profile More Agent Frameworks →

How to read this: HVTrust (0–100) weighs supply-chain signals (provenance, OSSF Scorecard, signed commits, open license) alongside real-world adoption, scaled by an evidence-confidence factor. Grade bands: A ≥ 80, B ≥ 65, C ≥ 50, D < 50. Signals refresh daily. Full methodology v4.4 →