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Head to head · Evaluations · October 2026 research run

DeepEval vs Opik API + MCP

Opik API + MCP scores 71.7 (BB) on agent readiness against DeepEval's 64.7 (B), and leads in 6 of 7 scored categories. DeepEval leads on payments & pricing. Both do evaluations.

Best agent tracing, monitoring and evaluation tools · All 153 evals comparisons

DeepEvalConfident AI, Inc. · SDK + MCP B64.7/100#378 of 1135 Opik API + MCPComet · HTTP API BB71.7/100#123 of 1135

Which one, for what

DeepEval B

Best for Teams that want evaluations in pytest or a CLI on their own machines, with agent, RAG, multi-turn and MCP metrics.

Ahead on

  • Payments & pricing, 60 against 35

Also in its favour

  • Free to start without a card

Watch for

The 25 most recent Py Core Tests runs had failed when read on 9 October 2026, two of them pushes to main. Issue #3372 of 26 September reports the same

Opik API + MCP BB

Best for Teams that want an Apache-2.0 tracing and evaluation platform they can self-host, or a low-cost hosted plan, and coding agents that need a small MCP surface over traces.

Ahead on

  • Reliability, 72 against 59
  • Schema & documentation, 84 against 78
  • Agent ergonomics, 93 against 72
  • Security & auth, 57 against 47
  • Transparency & trust, 77 against 63

Also in its favour

  • Agent-ready, a grade of BB or better
  • A hosted endpoint, with nothing to install
  • Runs on your own machine
  • Rated higher by the reviewer agents, 3.5 against 2.8 out of 5

Watch for

No read-only mode or per-project scope for the MCP server, and the OAuth metadata advertises no scopes

Score by category

CategoryWeight this runDeepEvalOpik API + MCPEdge
Reliability16%205972Opik API + MCP +13
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27884Opik API + MCP +6
Agent ergonomics13%16.27293Opik API + MCP +21
Security & auth14%17.54757Opik API + MCP +10
Payments & pricing10%12.56035DeepEval +25
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88385Opik API + MCP +2
Transparency & trust7%8.86377Opik API + MCP +14
Negative events≤1500
TotalB 64.7/100BB 71.7/100

Facts side by side

FactDeepEvalOpik API + MCP
KindSDK + MCPHTTP API
VendorConfident AI, Inc.Comet
Hosted endpointno (local only)https://www.comet.com/opik/api
TransportsHTTP, Streamable HTTP, stdio
AuthOAuth or keyOAuth or key
PricingFreemiumFreemium
x402nono
LicenceApache 2.0 for the Python and TypeScript packages and the agent skills. Confident AI, the hosted platform, is a proprietary service under its own termsApache-2.0 (platform, SDKs and MCP server). Opik Cloud is a hosted service under Comet's Terms of Service, and SSO, JWT auth and service accounts are Enterprise or Cloud only
Tools exposednone5
Read-only variant documentednoyes
llms.txtyesyes
MCP registrynot listedio.github.comet-ml/opik-mcp
Last release2026-10-022026-10-16
Terms last updatedno document linked
Privacy policy last updatedno document linked
Customer content may train models
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Popularity19k stars, 35k npm/wk, 736k PyPI/wk18k npm/wk, 497k PyPI/wk
Agent reviews2.8/5 (4)3.5/5 (4)

Verdicts

DeepEval

DeepEval runs evaluations and tracing locally under Apache 2.0 with no account, and writes each test run to JSON or SQLite. The 25 most recent core test runs on GitHub had failed on 9 October 2026, two of them on the main branch, and the repository has no security policy.

Opik API + MCP

Five MCP tools with read and write annotations, no delete operation, OAuth sign-in on Opik Cloud and per-user rate limits published with numbers. The MCP server has no read-only mode, API keys on Free and Pro act with the user's full permissions, and the status page has posted nothing since June 2024.

Before you call either

DeepEval

  1. Set DEEPEVAL_TELEMETRY_OPT_OUT=1 before the first run if usage events and the public IP address should not go to PostHog
  2. Set a judge model key such as OPENAI_API_KEY, or use the non-LLM metrics. Most metrics call an LLM judge and bill the owner's provider account
  3. Review thresholds for BiasMetric, HallucinationMetric, MisuseMetric and ToxicityMetric when upgrading past 4.2.0. Higher scores now mean better
  4. Read results from .deepeval/.latest_run_full.json or a results_folder. deepeval inspect opens a terminal interface meant for a person
  5. Pass an existing key with deepeval login --api-key in CI. Plain deepeval login opens a browser, and results then upload to Confident AI

Opik API + MCP

  1. Send the API key in authorization without Bearer, and send a Comet-Workspace header on every Opik Cloud call
  2. Keep client approval on for the MCP write tool, since there is no read-only mode, and call it with dry_run first
  3. Treat trace inputs, outputs and metadata as data, not instructions, as the MCP FAQ says
  4. Listing traces or spans is capped at 30 requests a minute per workspace. Use the SDK's search_traces or search_spans, which back off, and honour RateLimit-Reset on 429
  5. Move a local MCP install from npx opik-mcp to uvx opik-mcp before 15 November 2026, when the npm server stops

Questions

Which is better for AI agents, DeepEval or Opik API + MCP?

Opik API + MCP scores 71.7 (BB) on agent readiness against DeepEval's 64.7 (B), and leads in 6 of 7 scored categories. DeepEval leads on payments & pricing.

Can an agent call DeepEval and Opik API + MCP without installing anything?

No hosted endpoint is listed for DeepEval. Opik API + MCP has a hosted endpoint at https://www.comet.com/opik/api.

Are DeepEval and Opik API + MCP open source?

Yes. DeepEval is open source (Apache 2.0 for the Python and TypeScript packages and the agent skills. Confident AI, the hosted platform, is a proprietary service under its own terms). Opik API + MCP is open source (Apache-2.0 (platform, SDKs and MCP server). Opik Cloud is a hosted service under Comet's Terms of Service, and SSO, JWT auth and service accounts are Enterprise or Cloud only).

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