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Head to head · Analytics experiments · October 2026 research run

GrowthBook vs Optimizely Experimentation

GrowthBook scores 70.1 (BB) on agent readiness against Optimizely Experimentation's 62.6 (B), and leads in 6 of 7 scored categories. Both do analytics experiments.

GrowthBookGrowthBook, Inc. · HTTP API BB70.1/100#142 of 722 Optimizely ExperimentationOptimizely · HTTP API B62.6/100#330 of 722

Which one, for what

GrowthBook BB

Good for Teams that want flags and experiments analysed against their own warehouse, with an open-source core and a self-hosted option.

Ahead on

  • Reliability, 86 against 73
  • Agent ergonomics, 76 against 68
  • Payments & pricing, 40 against 0
  • Maintenance & community, 89 against 78

Also in its favour

  • Agent-ready, a grade of BB or better
  • Runs on your own machine
  • Free to start without a card
  • Open source

Watch for

The API tools take a path and a JSON string and don't validate payloads, so correct calls depend on the bundled skills

Optimizely Experimentation B

Good for An agent working for an existing Optimizely customer that lists and creates flags, experiments and audiences, reads experiment results and writes SDK integration code.

Also in its favour

  • No incidents deducted, where GrowthBook loses 3 points for them

Watch for

No price is published. The plans page says every plan is individually packaged and leads to a demo request

Score by category

CategoryWeight this runGrowthBookOptimizely ExperimentationEdge
Reliability16%208673GrowthBook +13
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27674GrowthBook +2
Agent ergonomics13%16.27668GrowthBook +8
Security & auth14%17.56866GrowthBook +2
Payments & pricing10%12.5400GrowthBook +40
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88978GrowthBook +11
Transparency & trust7%8.87475Optimizely Experimentation +1
Negative events≤15-30
Total70.1 · BB62.6 · B

Facts side by side

FactGrowthBookOptimizely Experimentation
KindHTTP APIHTTP API
VendorGrowthBook, Inc.Optimizely
Hosted endpointhttps://mcp.growthbook.io/mcphttps://exp.mcp.opal.optimizely.com/mcp
TransportsHTTP, Streamable HTTP, stdioHTTP, Streamable HTTP
AuthOAuth or keyOAuth or key
PricingFreemiumPaid
x402nono
LicenceMIT for the core and for the MCP server. Three enterprise directories in the main repository are under GrowthBook's enterprise licence. GrowthBook Cloud is a hosted service under the Customer AgreementProprietary hosted service under Optimizely's Online Software Subscription Agreement and its API, SDK and MCP terms. The Feature Experimentation SDKs on GitHub are Apache 2.0
Tools exposed47
Read-only variant documentednono
llms.txtyesyes
MCP registryio.github.growthbook/growthbook-mcpnot listed
Last release2026-10-062026-09-18
Terms last updated2025-06-19no date given
Privacy policy last updated2026-06-08no date given
Customer content may train modelsyesnot found in the text
Terms restrict automated accessnot found in the textnot found in the text
Terms restrict benchmarkingyesyes
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waivernot found in the textnot found in the text
Popularity8.5k stars, 1.3M npm/wk, 433k PyPI/wk460k npm/wk, 86k PyPI/wk

Verdicts

GrowthBook

GrowthBook Cloud's MCP server has four tools with read and write annotations, OAuth with dynamic client registration, and a 414-operation OpenAPI spec behind it. The free plan needs no card. The API tools pass paths and JSON bodies through without validation, every key is limited to 60 requests a minute, and audit logs are Enterprise only.

Optimizely Experimentation

Optimizely Experimentation suits agents working for an existing customer that manage flags and experiments and read results. The hosted MCP server has seven tools behind OAuth and carries the user's permissions, and the main REST API has a public Swagger spec. No price, free plan or trial is published, and no 429 or idempotency guidance was found.

Before you call either

GrowthBook

  1. Connect to https://mcp.growthbook.io/mcp and complete OAuth in a browser. Use https://mcp.growthbook.io/mcp/api for the two API tools alone
  2. Call growthbook_list_skills and growthbook_read_skill before writing. The API tools don't validate payloads, so use the paths the skill names
  3. Stay under 60 requests a minute per key. On 429 wait for the RateLimit-Reset seconds before retrying
  4. List calls return 10 items by default. Pass limit up to 100 and offset to page
  5. A 422 is a soft warning. Resubmit with ?ignoreWarnings=true only after reading the message

Optimizely Experimentation

  1. Connect to https://exp.mcp.opal.optimizely.com/mcp and complete OAuth in a browser. The session is time-limited, so expect to sign in again
  2. Call exp_get_schemas before exp_execute_query, and exp_get_entity_templates before exp_manage_entity_lifecycle, to learn the fields each entity needs
  3. Confirm the project and environment with the user before any create or update. Changes go to live Optimizely data
  4. Use the Visual Editor for Web Experimentation variation code. The MCP server does not write custom HTML, CSS or JavaScript
  5. Over REST, stay under 2 requests a second on /flags/v1, 100 a minute on /v2 and 20 a minute on the results endpoints

Questions

Which is better for AI agents, GrowthBook or Optimizely Experimentation?

GrowthBook scores 70.1 (BB) on agent readiness against Optimizely Experimentation's 62.6 (B), and leads in 6 of 7 scored categories.

Do GrowthBook and Optimizely Experimentation need an API key?

Both take an API key or an OAuth sign-in.

Can an agent call GrowthBook and Optimizely Experimentation without installing anything?

Yes. GrowthBook has a hosted endpoint at https://mcp.growthbook.io/mcp and Optimizely Experimentation at https://exp.mcp.opal.optimizely.com/mcp.

Are GrowthBook and Optimizely Experimentation open source?

GrowthBook is open source (MIT for the core and for the MCP server. Three enterprise directories in the main repository are under GrowthBook's enterprise licence. GrowthBook Cloud is a hosted service under the Customer Agreement). No open-source release is listed for Optimizely Experimentation.

Other comparisons with GrowthBook or Optimizely Experimentation

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