Experiment Planner

Design a bounded marketing or conversion experiment with a supplied meaningful effect, feasible traffic, guardrails, and a predeclared decision rule.

Conversion & experimentsWorks with exports or live data

When to use it

Before launching a test whose business effect, traffic, guardrails, and decision rule need definition.

Try asking

“Plan a four-week A/B test for our lead form and check whether the target lift is detectable from our baseline conversion rate.”

What you get back

An experiment brief with hypothesis, randomization, metric/guardrail definitions, feasibility, fixed horizon, and a launch boundary.

Fictional example output

The requested four-week horizon is insufficient for the stated planning assumptions. Baseline submit rate is 100/1,000 = 10.00%. The meaningful target is 12.00%: +2.00 percentage points, or +20.00% relative.

The optional binary normal-approximation calculator requires approximately 3,841 independent units per arm, 7,682 total, for two-sided alpha .05 and power .80. At 1,000 eligible users/week with a 50/50 split, enrollment requires about 7.682 weeks, plus 7 days for the final cohort to mature. Four weeks supplies only about 2,000 users per arm.

Design: change only form fields; assign users consistently, analyze accepted submissions per eligible assigned user at the fixed horizon, check instrumentation before enrollment, and predeclare the qualification guardrail. The approximate sample estimate is not a guarantee and is invalid for clustered users or repeated dependent trials.

Decide whether to extend the enrollment horizon, seek additional eligible traffic, or revise the user-selected effect criterion. Do not launch a four-week test with a promised winner. No experiment created and no auto-apply enabled.

Fictional data. An illustration of the method, not a customer result.

Where the data comes from

Connected with Orphex Recommended

The skill reads your connected accounts for the right dates. Nothing to export or upload.

Connect free
Input columns 8 required, 0 optional
experiment_idRequired
Proposed bounded experiment identifier
baseline_trialsRequired
Eligible independent baseline units
baseline_successesRequired
Unique binary outcomes in those baseline units
weekly_eligible_trialsRequired
Observed feasible traffic before splitting
target_rateRequired
User-supplied meaningful treatment rate, fraction 0–1
alphaRequired
Supplied two-sided false-positive criterion
powerRequired
Supplied desired detection probability under planning assumptions
outcome_delay_daysRequired
Required follow-up/reporting delay after the last enrolled unit
Before you start 2 items
  • Supplied data with the documented task-specific columns, stable scope, and refresh/maturity context
  • Business definitions and constraints relevant to the decision; see the reusable business-context reference

Supply your objectives, conversion definitions, currency, constraints, and approved brand facts once, then reuse the profile across reviews. Leave unknown values explicit.

Open profile source
The method

With an Orphex connection

If an Orphex connector is available, check it before asking for exports. Run capability_search with platform orphex and limit 100; use a read only if that search returns its id, and ask which workspace to use when several are bound. Read controller.catalog then controller.fetch at the planned unit's level for baseline volume, conversion rate and day-to-day variation over a comparable recent window. Then list guides with skill_catalog (kind guide, topic measurement) and follow a matching one through skill_read; choose by title, never by a stored id.

Source and evaluation v2.1.0 · MIT
View SKILL.md

Orphex Experiment Planner

Turn a specific business uncertainty into a feasible experiment brief. Preserve the user's chosen scope and meaningful effect; do not add unrelated variants or guarantee a winner.

With an Orphex connection

If an Orphex connector is available, check it before asking for exports. Run capability_search with platform orphex and limit 100; use a read only if that search returns its id, and ask which workspace to use when several are bound. Read controller.catalog then controller.fetch at the planned unit's level for baseline volume, conversion rate and day-to-day variation over a comparable recent window. Then list guides with skill_catalog (kind guide, topic measurement) and follow a matching one through skill_read; choose by title, never by a stored id.

If a read is not returned, this connection cannot reach that Orphex data for the workspace: say so, then use the live platform reads it offers or the supplied exports. An absent, refused or empty read is not evidence of zero, none or healthy. Describe each read with capability_describe before run_read, keep date_end no later than yesterday, disclose request adjustments, and name each number's source, workspace and window. This skill's evidence rules still govern any guide, insight or playbook label, and no read authorizes account changes. Ask the user only for what is still missing.

Define the estimand and design

State the one change, hypothesis, eligible population, unit of randomization, control/treatment, primary outcome numerator and denominator, attribution/follow-up, and the smallest effect worth acting on. Separate a relative lift from percentage points. Specify consistent assignment, contamination risk, excluded units, instrumentation checks, guardrails, and the analysis horizon before launch. An optimized creative delivery comparison is not randomized assignment; platform experiment types and supported campaign/goal combinations must be verified for the actual account.

Keep outcome follow-up, conversion maturation, reporting/import delay, and attribution model/lookback as separately named definitions. A supplied seven-day outcome or reporting lag does not establish a seven-day attribution window. Preserve the supplied label and leave an unsupplied attribution rule unknown; do not fill it with a platform default when writing the brief.

For a simple independent binary outcome with two equal arms, use the optional calculator for an approximate fixed-horizon sample estimate from baseline rate, target rate, alpha, and power supplied by the user. State assumptions and round enrollment upward. Do not use that calculation for revenue/CPA means, clustered geographies, repeated users, sequential monitoring, multiple variants, or heavy-tailed outcomes; use an appropriate documented method or report that feasibility remains unquantified. Baseline zero/one or missing traffic requires different evidence, not fabricated defaults.

For a baseline-sensitivity scenario, explicitly state whether the absolute effect, relative effect, or target rate is held fixed and recompute the sample requirement under that convention. A lower baseline does not universally increase required sample: both outcome variance and the distance to the specified target matter. Do not make a directional sample or power claim from a changed baseline alone, or silently switch effect conventions. Alternative meaningful-effect criteria require the user's approval before they replace the supplied decision question.

Compare required sample with actual eligible traffic after allocation and add outcome/reporting maturation. A business deadline is not evidence of sufficient power. If infeasible, present the tradeoff: more traffic/time, a different user-approved effect criterion, or a descriptive pilot. Do not weaken the criterion silently. Predeclare what happens for inconclusive, guardrail-failing, or invalid results, including stop conditions for operational faults and a rollback reference.

Distinguish an enrollment deadline from a fully mature result deadline. For a result deadline, subtract required outcome follow-up and reporting lag from the available calendar horizon before calculating traffic needed for enrollment. Derive a traffic requirement only when that remaining enrollment window is positive. If the result horizon is no longer than the required lag, increasing traffic cannot create a positive enrollment window for a new fully mature trial. Extend the result deadline, clarify that the deadline concerns enrollment only, or offer a clearly descriptive pilot; sample sufficiency alone does not establish deadline feasibility.

Deliver a reviewable brief

Include hypothesis, assigned units, metric, guardrails, sample assumptions, dates/lag, exclusions, and the decision rule. Keep creation, edits, and rollout proposal-only without specific authorization. Check platform auto-apply settings rather than assuming a scheduled test cannot mutate campaigns.

Official reference

Portable inputs and examples

State whether the result is complete, partial, or blocked for the requested decision. Link material findings to actual supplied rows/sources and separate observed metrics, hypotheses, and estimates. Lead with a short business conclusion, then evidence, uncertainty, and the next measurable check. A data export or installed skill does not authorize account changes.

For the supported arithmetic only, optionally run the bundled calculator with Python 3: python3 scripts/marketing_math.py experiment < calculation.json. Read its input mapping in the input contract before preparing JSON. It reads JSON, not CSV directly. If Python or the requested method is unavailable, show a reproducible alternative calculation or mark it unsupported; do not report an uncomputed result as verified.

View on GitHub Open SKILL.md

How this release was evaluated

See the recorded checks, compared runs, results, and limits for v2.1.0. Example reviews illustrate the method; they do not guarantee account results.

Read the evaluation report