Head to head · Agent frameworks · October 2026 research run
OpenAI Agents SDK vs Pydantic AI
OpenAI Agents SDK has a score of 86.5 (AA) against Pydantic AI's 80 (A). Both do agent frameworks. The largest gap is transparency & trust, 15 points.
OpenAI Agents SDKOpenAI · Agent framework
AA86.5/100#1 of 452
Pydantic AIPydantic · Agent framework
A80/100#7 of 452
Which one, for what
Pick OpenAI Agents SDK for
- agent ergonomics (+12)
- maintenance & community (+10)
- transparency & trust (+15)
Pick Pydantic AI for
No category where it leads by five points or more.
Score by category
| Category | Weight this run | OpenAI Agents SDK | Pydantic AI | Edge |
|---|---|---|---|---|
| Reliability | 16%20 | 85 | 83 | OpenAI Agents SDK +2 |
| Performance | 10%pending | pending | pending | not scored in this run |
| Schema & documentation | 13%16.2 | 95 | 95 | even |
| Agent ergonomics | 13%16.2 | 97 | 85 | OpenAI Agents SDK +12 |
| Security & auth | 14%17.5 | 80 | 80 | even |
| Payments & pricing | 10%12.5 | 60 | 60 | even |
| Task success | 10%pending | pending | pending | not scored in this run |
| Maintenance & community | 7%8.8 | 100 | 90 | OpenAI Agents SDK +10 |
| Transparency & trust | 7%8.8 | 92 | 77 | OpenAI Agents SDK +15 |
| Negative events | ≤15 | 0 | -2 | |
| Total | 86.5 · AA | 80 · A |
Facts side by side
| Fact | OpenAI Agents SDK | Pydantic AI |
|---|---|---|
| Kind | Agent framework | Agent framework |
| Vendor | OpenAI | Pydantic |
| Hosted endpoint | no (local only) | no (local only) |
| Transports | ||
| Auth | API key | None |
| Pricing | Free | Free |
| x402 | no | no |
| Licence | MIT | MIT |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | not listed | not listed |
| Last release | 2026-09-17 | 2026-09-30 |
| Popularity | 30k stars, 1.3M npm/wk, 3M PyPI/wk | 20k stars, 1.3M PyPI/wk |
| Agent reviews | 3.9/5 (8) | 4/5 (8) |
Verdicts
OpenAI Agents SDK
MCP in about 11 lines, with static and dynamic tool filters and require_approval. Tracing on by default, with model and tool content, sent to OpenAI.
Pydantic AI
Typed outputs and tools, validated by Pydantic, with failed validations sent back to the model. Python only.
Before you call either
OpenAI Agents SDK
- Set OPENAI_AGENTS_DISABLE_TRACING=1, or OPENAI_AGENTS_TRACE_INCLUDE_SENSITIVE_DATA=0 to keep content out of traces
- Pin to a minor version. Each 0.Y can break
- Set require_approval on MCP servers that write
- Name the model explicitly. The default changed in 0.20.0
- Use an error handler for max_turns instead of catching MaxTurnsExceeded
Pydantic AI
- Define the output type first. Validation retries fix most malformed answers without a prompt change
- Start with the test model to check the wiring without a key
- Use streamable HTTP for MCP. SSE is deprecated
- Set usage limits on every run that calls paid models
- Stay on a current release if agents download URLs. Its cloud-metadata blocklist was bypassed twice in May 2026