Datadog vs Tessary
Datadog and Tessary are both uptime & monitoring tools. Datadog is aimed at enterprise and developers, while Tessary is aimed at developers and small businesses. Both have a free plan.
Cloud monitoring and security platform
Open-source monitoring that finds why production AI agents fail
| Pricing | Freemium · $18 | Open source |
| Starting price | $18/mo | Not published |
| Free plan | Yes | Yes |
| Free trial | 14 days | — |
| Built for | Enterprise, Developers | Developers, Small businesses, Enterprise |
| Platforms | web | web, linux |
| Country | US · 2010 | — |
| Rating | — | — |
Choose Datadog if
Scale-ups and enterprises running complex cloud infrastructure with budget for observability.
- Broadest observability coverage in one tool
- Excellent dashboards and correlation
- 900+ integrations
Look elsewhere if: Startups and small teams (Grafana Cloud free, Better Stack, Sentry).
Choose Tessary if
Engineering teams running AI agents in production with OpenTelemetry traces who want every trace checked and failures explained.
- Apache 2.0 open source with free self-hosting
- Checks every trace instead of a sampled subset
- RCA links failures to specific commits when a repo is connected
Look elsewhere if: Teams that want a mature, fully supported observability suite or an eval-first workflow (Datadog, Braintrust).
Datadog vs Tessary pricing
Datadog
- Free$0Up to 5 hosts, 1-day metric retention
- Infrastructure Pro$18/host/moOn-demand; $15 billed annually
- Infrastructure Enterprise$27/host/moOn-demand; $23 billed annually
- APM$36/host/moOn-demand; $31 billed annually with Infrastructure
- Log Management$0.10/GB ingestedIngest only; indexing billed separately
Tessary
- Open Source$0Self-host with Docker Compose; all core features
- Cloud Free$010k traces/mo, 1 GB, 30-day retention, $10 one-time RCA credit
- PaidCustomCustom classifiers, managed dedicated instance, Slack support
Datadog · Key features
- Infrastructure metrics and host maps
- APM, distributed tracing and continuous profiler
- Log management with pipelines and archives
- RUM, session replay and synthetic monitoring
- Security monitoring and cloud SIEM
- Incident management and Bits AI
Cons
- Expensive and complex pricing
- Costs grow with hosts and log volume
- Easy to overspend on custom metrics
Tessary · Key features
- Classifiers run on every production trace with no sampling
- Built-in checks for drift, tool errors, secret leaks and malformed output
- LLM triage groups real deviations into trackable cases
- Root-cause analysis over failing traces and your GitHub repository
- OTLP ingestion over HTTP and gRPC with OpenTelemetry gen_ai conventions
- PII redaction before traces are stored
Cons
- Very new project with a short track record
- Paid plan prices are not published
- Frustration classifier requires your own OpenRouter or TypeSafe key
Datadog vs Tessary: FAQ
Do Datadog and Tessary have a free plan?
Yes, both Datadog and Tessary have a free plan; paid plans add more usage and features.
Which is better for small businesses, Datadog or Tessary?
Tessary lists small businesses as a core audience, while Datadog is aimed more at enterprise and developers.