kitio.aiArthur vs Pydantic Logfire
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Pydantic Logfire has the lower starting price: about $49 a month, against $60 for Arthur.
At a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Agent discovery
- Step-level tracing
- Runtime guardrails
- Audit logs and lineage
- Custom metrics and alerts
- OpenTelemetry tracing
- LLM call views
- Auto-instrumentation
- SQL queries on traces
- Dashboards
| Feature | Arthur | Pydantic Logfire |
|---|---|---|
| Best for | Discovery, monitoring and governance for enterprise AI agents | OpenTelemetry observability for Python apps and AI agents |
| Category | Models & APIs | Models & APIs |
| Pricing model | Freemium | Freemium |
| Starting price | $60/mo | $49/mo |
| Free plan | Yes | Yes |
| Made by | Arthur AI | Pydantic |
| Based in | United States | United Kingdom |
| Rating | No ratings yet | No ratings yet |
| Key features |
|
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Pricing compared
Pydantic Logfire has the lower starting price: about $49 a month, against $60 for Arthur.
Free plan
Cheapest paid plan
Top plan
Free trial
3 plans
Free
Free
- Up to 4 monitored use cases
- Unlimited seats
- Cloud data connectors
Premium
$60/mo
- Up to 100 use cases
- Custom metrics and dashboards
- Custom alerts and webhooks
Enterprise
Contact sales
- Dedicated infrastructure
- Governance and support
4 plans
Personal
Free
- 10M records per month, hard-capped
- 3 projects, 30-day retention
- 1 seat + 2 read-only guests
Team
$49/mo
- 10M records included, $2/M after
- 5 seats included, $25/extra seat
- AI evaluations and human review
Growth
$249/mo
- Unlimited seats and projects
- Up to 90-day retention
- Priority support and BAA
Enterprise
Contact sales
- Compliance support
- Self-hosting options
Prices in USD, checked Oct 28, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
Arthur
- Finds shadow agents across environments
- Free tier with unlimited seats
- Covers security and evaluation together
- Free tier monitors only 4 use cases
- Enterprise features need a sales call
- Broad platform takes time to set up
Pydantic Logfire
- Full-stack plus LLM traces
- Easy setup for Python
- SQL access to data
- Python-first experience
- Fewer eval tools than rivals
- Volume pricing needs monitoring
Which one should you choose?
Choose Arthur if you want:
- Finds shadow agents across environments
- Free tier with unlimited seats
- Covers security and evaluation together
Watch out: free tier monitors only 4 use cases.
Choose Pydantic Logfire if you want:
- Full-stack plus LLM traces
- Easy setup for Python
- SQL access to data
Watch out: python-first experience.
Arthur vs Pydantic Logfire FAQ
What is the difference between Arthur and Pydantic Logfire?
Arthur: Discovery, monitoring and governance for enterprise AI agents. Pydantic Logfire: OpenTelemetry observability for Python apps and AI agents. Both are models & apis tools.
Is Arthur or Pydantic Logfire cheaper?
Pydantic Logfire has the lower starting price: about $49 a month, against $60 for Arthur.
Do Arthur and Pydantic Logfire have free plans?
Arthur: Yes. Pydantic Logfire: Yes.
Who makes Arthur?
Arthur is made by Arthur AI, based in United States.
Who makes Pydantic Logfire?
Pydantic Logfire is made by Pydantic, based in United Kingdom.
Which should I choose, Arthur or Pydantic Logfire?
Choose Arthur if you value finds shadow agents across environments and free tier with unlimited seats. Choose Pydantic Logfire if you value full-stack plus llm traces and easy setup for python.