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configs-variations

launchdarkly/ai-tooling

Create and test config variations to optimize models, prompts, and parameters through systematic experimentation.

What is configs-variations?

This skill helps you design and run experiments on AI configs by creating variations that test one variable at a time—such as switching models, adjusting prompts, or tuning parameters. Use it when you need to find the best configuration for cost, quality, speed, or accuracy.

  • Clone baseline configs with selective overrides to test single variables
  • Create variations from scratch with full control over all fields
  • Review existing variations before adding new ones
  • Update and refine variations after creation
  • Delete variations that didn't meet your goals

How to install configs-variations

npx skills add https://github.com/launchdarkly/ai-tooling --skill configs-variations
Prerequisites
  • LaunchDarkly MCP server configured in your environment
Claude Code
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How to use configs-variations

  1. 1.Identify what to optimize: cost, quality, speed, or accuracy
  2. 2.Design your experiment by deciding which single variable to test
  3. 3.Use clone-ai-config-variation to duplicate the baseline and override only the field you're testing
  4. 4.Verify the variation was created correctly by comparing source and new variation
  5. 5.Measure results against your hypothesis
  6. 6.Create additional variations for other hypotheses or refine existing ones

Use cases

Good for
  • Test a cheaper model (e.g., gpt-4o-mini) to reduce costs while maintaining quality
  • Compare different prompt instructions to improve output accuracy
  • Experiment with lower max_tokens to reduce latency
  • Switch between model families (Claude vs GPT-4) to measure quality differences
  • Run A/B tests on variations before rolling out to production
Who it's for
  • AI product managers optimizing model performance
  • Engineers tuning prompts and parameters
  • Teams managing cost vs. quality tradeoffs
  • Researchers comparing model families and configurations

configs-variations FAQ

Should I modify the baseline variation or create a new one?

Always create a new variation alongside the baseline. Never modify or delete the baseline—this preserves your ability to compare and safely roll back if needed.

Can I test multiple variables at once?

No. Change one variable per variation (either model, prompt, or parameters). Testing multiple variables at once makes it impossible to know which change caused the result.

What fields should I pass when cloning?

Pass only the fields you are testing (e.g., modelConfigKey and modelName for a model test). Leave all other fields unset so they inherit from the source variation automatically.

What is modelConfigKey and why does it matter?

modelConfigKey identifies the model in the format {Provider}.{model-id}, such as OpenAI.gpt-4o or Anthropic.claude-sonnet-4-5. Variations without it display as 'NO MODEL' in the UI.

How do I know if my variation was created successfully?

The clone tool returns both source and created variations for immediate comparison. Otherwise, use get-ai-config to verify the variation exists with the correct overrides.

Full instructions (SKILL.md)

Source of truth, from launchdarkly/ai-tooling.


name: configs-variations description: "Experiment with configs by creating and managing variations. Helps you test different models, prompts, and parameters to find what works best through systematic experimentation." license: Apache-2.0 compatibility: Requires the remotely hosted LaunchDarkly MCP server metadata: author: launchdarkly version: "1.0.0-experimental"

Config Variations

You're using a skill that will guide you through testing and optimizing configs through variations. Your job is to design experiments, create variations, and systematically find what works best.

Prerequisites

This skill requires the remotely hosted LaunchDarkly MCP server to be configured in your environment.

Primary MCP tool:

  • clone-ai-config-variation -- clone a baseline variation with selective overrides (recommended for experimentation)

Alternative MCP tools (for more control):

  • get-ai-config -- review existing variations before adding new ones
  • create-ai-config-variation -- create new variations from scratch

Optional MCP tools:

  • update-ai-config-variation -- refine a variation after creation
  • delete-ai-config-variation -- remove variations that didn't work out

Core Principles

  1. Test One Thing at a Time: Change model OR prompt OR parameters, not all at once
  2. Have a Hypothesis: Know what you're trying to improve
  3. Measure Results: Use metrics to compare variations
  4. Verify via Tool: The agent fetches the config to confirm variations exist

Workflow

Step 1: Identify What to Optimize

What's the problem? Cost, quality, speed, accuracy? How will you measure success?

Step 2: Design the Experiment

GoalWhat to Vary
Reduce costCheaper model (e.g., gpt-4o-mini)
Improve qualityBetter model or more detailed prompt
Reduce latencyFaster model, lower max_tokens
Increase accuracyDifferent model family (Claude vs GPT-4)

Step 3: Create Variations (Recommended: Clone with Overrides)

Use clone-ai-config-variation to duplicate the baseline and override only what you're testing. The tool reads the source variation, merges your overrides, and creates the new variation. Everything you don't pass is inherited from the source automatically.

Required fields:

  • sourceVariationKey -- the baseline to clone from
  • key and name -- identifiers for the new variation (e.g., gpt4o-mini-cost-test)

Override ONLY the fields you are testing. Leave all other fields unset -- do not pass them even if you know their current values. The clone tool inherits them from the source. This enforces the one-variable-at-a-time principle:

  • Testing a cheaper model? Pass only modelConfigKey and modelName. Do NOT pass instructions, messages, or parameters.
  • Testing different instructions? Pass only instructions. Do NOT pass modelConfigKey or modelName.
  • Testing a parameter? Pass only parameters. Do NOT pass model or prompt fields.

The response returns both the source and created variation, so you can immediately verify the diff.

Step 3 (Alternative): Create from Scratch

If you need full control, use get-ai-config first to review the current state, then create-ai-config-variation with all fields specified manually. Always fetch before creating so you understand the existing config's mode, model, and parameters.

Step 4: Verify

If you used clone-ai-config-variation, the response includes both source and created variations for immediate comparison. Otherwise, use get-ai-config to confirm.

Report results:

  • Variations created with correct models and parameters
  • Only the intended variable differs between variations
  • Flag any issues

Note on API responses: After calling a creation or clone tool, treat a successful response as confirmation that the operation succeeded. The API response may not echo back every field you sent (e.g., model fields may show defaults). Do not retry or assume failure based on response field values alone -- verify with get-ai-config if needed.

modelConfigKey Format

Required for models to display in the UI. Format: {Provider}.{model-id}:

  • OpenAI.gpt-4o, OpenAI.gpt-4o-mini
  • Anthropic.claude-sonnet-4-5, Anthropic.claude-3-5-sonnet

Safety: Protect the Baseline

When the user wants to try a different model, prompt, or parameters, always create a new variation alongside the baseline. Never modify or delete the existing baseline variation. This applies even if the user says "replace" or "switch" -- the correct action is to create a new variation and let targeting/rollouts control traffic, not to edit the original.

  • Use clone-ai-config-variation or create-ai-config-variation to add the new variation
  • Do NOT use update-ai-config-variation on the baseline to change its model or instructions
  • Do NOT use delete-ai-config-variation on the baseline
  • Explain to the user that keeping the baseline enables comparison and safe rollback

What NOT to Do

  • Don't test too many things at once -- change one variable per variation
  • Don't pass unchanged fields when cloning -- let the tool inherit them from the source
  • Don't forget modelConfigKey (variations without it show as "NO MODEL" in the UI)
  • Don't make decisions on small sample sizes
  • Don't modify or remove the baseline variation -- create new variations alongside it
  • Don't use update-ai-config-variation to "replace" a baseline -- create a new variation instead

More resources

To learn more about creating and managing variations, read Create and manage config variations.

Related Skills

  • configs-create -- Create the initial config
  • configs-update -- Refine based on learnings