The working relationship is simple: experimentation creates the evidence; evaluation measures the result.
Together they tell a product team what to ship. Lovelaice is an AI quality evaluation platform for product teams; AI experimentation is the workflow the team uses to reach a defensible decision on its own data, for its own users, against its own quality criteria.
What AI experimentation is
An AI experiment is a controlled comparison designed to answer a product decision. It might ask whether a revised claims-extraction prompt is safer than the current version, whether a smaller model can meet the same quality threshold at lower cost, or whether giving an agent a calculator reduces policy errors. The decision comes first. The models, prompts and scores exist to inform it.
A useful experiment contains a stated decision or hypothesis, a representative dataset, a baseline, one or more controlled variants, and quality criteria written before the team reviews aggregate results. It uses human or automated evaluation to judge real outputs. When the feature will run at meaningful volume, it also records cost and latency. It ends with limitations and a decision: select, reject, iterate or collect more evidence.
Sending one prompt to several chatbots and choosing the answer that looks best is not an experiment. It is a useful first encounter with the problem, but the choice is exposed to cherry-picking, brand preference and an input that may flatter one configuration. A controlled comparison runs every plausible variant against the same cases and rubric. It makes an improvement visible across the set and makes regressions difficult to ignore.
Teams can enter this workflow at very different points. In Lovelaice’s work with product teams, one team may arrive with a two-sentence idea and no expected outputs. Another may already operate an OCR, computer-vision or chatbot workflow and need to compare an LLM-based replacement. The first team needs rapid learning; the second needs careful baseline preservation. Both need an explicit decision and evidence proportionate to its consequences.
Four nearby practices, separated
| Practice | Primary question | Typical evidence | Relationship |
|---|---|---|---|
| AI experimentation vs AI evaluation | Which configuration should we choose? | Controlled comparison across a fixed test set. | Evaluation supplies the judgment inside the experiment. |
| AI experimentation vs A/B testing | Is the output good enough, and then do users respond better? | Offline output review before exposure; behavioural data after exposure. | Use offline experiments as a quality gate, then A/B test user impact where appropriate. |
| AI experimentation vs prompt testing | Did this instruction change improve results? | Prompt variants under fixed model and evaluation conditions. | Prompt testing is one experiment type; models, retrieval and workflows can vary too. |
| AI experimentation vs AI observability | What is happening in the live system? | Production traces, errors, latency, cost and sampled quality. | Observability finds production signals; experimentation reproduces failures and validates a change before release. |
Why conventional product experimentation is insufficient
Traditional A/B testing measures what users do after they see a variant. AI experimentation must also inspect what the system says or does before users are exposed. A conventional interface variant is normally deterministic: the button is blue every time. An AI feature can return a fluent, plausible and wrong result, then return a different result for the same input. That makes output quality a pre-release product concern.
“Ship and learn” becomes risky when the failure is silent. A user may not report that a recommendation was mediocre, a contract summary omitted a clause, an extracted invoice moved a decimal, or a lead classifier assigned the wrong tier. The interface can work, the request can return successfully and the product analytics can look normal. Trust erodes without a neat error event. In high-consequence workflows, the user may act on the answer before anyone notices.
This does not make online experiments obsolete. Offline AI experimentation and A/B testing answer different layers of the same product question. First verify that candidate outputs meet a product-specific quality and safety threshold on controlled cases. Then, where responsible, measure whether the qualified variant improves completion, adoption, retention or another user outcome. A variant that drives clicks while quietly making worse decisions is not a product win.
Nor is the goal certainty before release. No offline set recreates every production input. The goal is to replace “ship and hope” with a bounded claim: on these representative cases, under these conditions, this version cleared the threshold, improved on the baseline, and retained these known weaknesses. Production monitoring then tests whether the claim continues to hold.
What teams can vary
An AI feature is a system of choices, not a model name. Teams can vary the prompt, model, retrieval, tools, workflow, generation settings, context, output format and evaluator pairing. A clean experiment changes the variable needed to answer the decision while keeping other influential conditions fixed. When two elements must change together, document the combined configuration rather than pretending the result isolates one cause.
| Variable | Question it answers | Keep fixed | Metrics that matter |
|---|---|---|---|
| Prompt version | Does a change in instructions improve the intended behaviour? | Model version, dataset, settings, context, tools and rubric. | Rubric scores, regressions, failure types, tokens and latency. |
| Model and model version | Which production-feasible model handles this task best? | Prompt, dataset, context, settings where comparable and rubric. | Quality by segment, failure severity, cost, latency and stability. |
| Retrieval configuration | Which sources, chunking or retrieval rules supply useful evidence? | Prompt, model, query set, tool access and evaluation criteria. | Retrieval recall, groundedness, answer quality, cost and latency. |
| Available tools | Does access to a search, calculator or product action improve outcomes? | User task, model, instructions, dataset and success criteria. | Task completion, correct tool choice, unsafe actions and latency. |
| Agent workflow | Which sequence of instructions, hand-offs and checks works reliably? | Goal, input set, tools, underlying models and acceptance threshold. | Completion, step failures, recovery, total cost and end-to-end time. |
| Generation settings | Do temperature, output length or sampling controls improve consistency? | Prompt, model version, dataset, context and rubric. | Repeat-run variance, quality, format compliance, cost and latency. |
| Context | Which user, domain or conversation context is necessary? | Prompt structure, model, test cases and quality criteria. | Correctness, personalization, privacy risk, tokens and failure patterns. |
| Output format | Which response structure best supports the user and downstream system? | Meaning of the instructions, model, dataset and evaluation rubric. | Schema compliance, usefulness, completeness and parsing failures. |
| Evaluator pairing | Which rubric and judge model reproduce expert judgment? | Human-labelled set, output contract, sampling controls and failure definition. | Agreement, false positives, false negatives, reasons and repeatability. |
The table is a design aid, not a demand to test everything. If the decision is whether retrieval source A or B answers support questions more accurately, there is little value in simultaneously changing the model, response format and agent instructions. If the decision is which production configuration to ship, testing a short list of complete pairings can be appropriate—but each pairing and its differences must be named.
The Lovelaice AI Experimentation Loop
The loop turns an uncertain AI idea into a repeatable product decision. Each step has a concrete output: a decision statement, test set, rubric, baseline, controlled change, reviewed outputs, failure analysis, decision record and regression run. A small exploratory experiment can complete the loop quickly; a high-risk release will deepen every step.
- 01
Define the decision.
State what the team must decide and why it matters to users or the business.
- 02
Build the test set.
Combine representative inputs, edge cases, and high-cost failure cases.
- 03
Define “good.”
Write the domain-specific rubric and acceptance threshold before seeing aggregate results.
- 04
Create the baseline.
Record the current prompt, model, output quality, cost, latency, and known failures.
- 05
Change one variable.
Keep the dataset and evaluation conditions constant wherever the question permits.
- 06
Review real outputs.
Use blind side-by-side review when model identity could bias judgment; record why each output fails.
- 07
Analyse failure patterns.
Group errors by frequency, severity, and user impact.
- 08
Decide and document.
Select, reject, or iterate; retain the evidence and known limitations.
- 09
Repeat against the baseline.
Re-run the evaluation suite before shipping each material change.
How to use the nine steps
1. Define the decision. Write the choice in a form that can conclude with select, reject, iterate or gather more evidence. “Test GPT-5” is an activity. “Decide whether the lower-cost model can replace our current classifier without increasing missed high-risk cases” is a decision tied to users and the business.
2. Build the test set. Combine common inputs, known edge cases and cases where a wrong answer is expensive. Record where each case came from, which segment it represents, and what information has been removed or reconstructed. The set should expose the decision, not merely demonstrate that the system can produce a good-looking answer.
3. Define “good.” Write the rubric and acceptance threshold before aggregate results can influence them. Separate necessary conditions from preferences. A medical summary might require factual fidelity and omission coverage; concise wording may be secondary. If one failure can cause material harm, an average score must not hide it.
4. Create the baseline. Run the current production configuration or the simplest credible starting point. Record prompt and model versions, output quality, cost, latency and known failures. Without a baseline, a candidate can look impressive while delivering no meaningful improvement over what already exists.
5. Change one variable. Keep the dataset and evaluation conditions constant wherever the question permits. Version every material input. If a model requires a materially different prompt to be viable, treat the prompt × model combination as a named variant and compare complete configurations honestly.
6. Review real outputs. Use blind review when model identity or version reputation could bias judgment. Side-by-side outputs are especially useful early: experts can identify which response handles a nuance better and explain why. Record the reason for every fail, not only the score.
7. Analyse failure patterns. Group review notes by type, frequency, severity, affected segment and likely cause. Ten formatting failures may deserve a deterministic validator; one rare but severe authorization error may block release. The point is to choose the next product change, not create a decorative taxonomy.
8. Decide and document. Select, reject or iterate. Keep the evidence, limitations and minority opinions. A decision record should be understandable to someone who did not attend the review and should distinguish measured facts from interpretation.
9. Repeat against the baseline. Re-run the relevant evaluation suite before every material release. A prompt improvement can reopen a failure elsewhere; a provider update can change behaviour; a new retrieval source can alter both quality and latency. The stable comparison point is the version the product currently trusts.
How many cases?
Start with 3–5 realistic cases to learn what prompts and models actually do. Expand to approximately 20–50 carefully selected cases to find recurring failures and establish an initial baseline. Use larger validation sets, repeated runs and stronger segment coverage when risk, variability or the shipping decision demands them. Sample size follows the decision and its consequences; there is no universal magic number.
Designing a representative dataset
A representative dataset is a deliberately selected model of the product’s work. It includes real inputs, or realistically reconstructed inputs when privacy prevents direct use, and preserves the variation that could change the decision. It is not a random export assumed to be representative, and it is not a polished demo set made entirely of cases the feature already handles.
Begin with common cases so the experiment reflects the experience most users will have. Add known edge cases from support, QA, domain experts and production incidents. Add adversarial or stress cases that challenge instruction boundaries. Identify errors with asymmetric consequences: a false positive may be tolerable in one workflow while a false negative creates compliance exposure in another. Segment by the dimensions that change meaning—user type, language, document type, jurisdiction, conversation length or workflow stage.
Each case needs either an expected output or acceptance criteria. Exact expected values work for extraction fields and classifications. Open-ended recommendations usually need a rubric: required facts, prohibited claims, acceptable tone and a written account of what would make the output useful. Record uncertainty rather than forcing false precision. If experts legitimately disagree, preserve the disagreement and clarify which product policy resolves it.
Treat privacy as part of experiment design. Use the minimum data needed, redact identifiers consistently, restrict access, document transformations and verify that redaction does not remove the clues the product depends on. Synthetic cases can fill a coverage gap, but label them as reconstructed and do not present their results as production prevalence.
Worked example: expense-policy decisions
Suppose a team is deciding whether an AI agent can approve routine employee expenses. A weak set contains five ordinary restaurant receipts below the limit. A useful exploratory set also includes a receipt just above the limit, a missing attendee, a permissible exception, a duplicated charge, an ambiguous currency and a senior employee who should not receive different policy treatment. Each case includes the policy clause, expected approve/reject/escalate decision, and what evidence the explanation must cite.
Run the current prompt as baseline, then compare one structured prompt change on the same cases. Review decisions and reasons separately: the right decision for a fabricated reason is not trustworthy. The documented Lovelaice expense-policy experiment used seven cases, three prompt versions and six models—126 runs. Its best documented configuration reached six correct decisions out of seven, but seven cases remain exploratory evidence, not production readiness. Read the expense-policy experiment and limitations.
Defining product-specific quality
Product-specific quality describes the decision your product exists to make. Generic “helpfulness,” “relevance” or “hallucination” scores can be useful prompts for discussion, but they often miss the operational distinction users care about. A lead-qualification agent can sound helpful while assigning the wrong priority. A contract summary can be relevant while omitting the termination clause. A policy answer can be factually grounded while choosing the wrong exception.
Start in the language of domain expertise. Ask reviewers what would make the output unsafe, unusable or misleading; what must always be present; which mistakes deserve escalation; and whether some failures cost more than others. Turn those answers into observable rubric items. “Good answer” is difficult to apply consistently. “Names the controlling policy clause, reaches the correct decision and does not invent an exception” is reviewable.
Lovelaice’s battle of the LLM judges shows why the rubric must come from the product. The case study covered one lead-qualification product, 34 real responses with 17 correct and 17 incorrect human labels, eight judge prompts, ten models and two complete runs, producing more than 5,000 verdicts. The best purpose-built prompt × model pairing reached 76.5% agreement with the human expert. Seven generic templates averaged 52–58%, and approximately 8% of identical verdicts changed between runs.
Those numbers are not a universal benchmark for judge vendors, model families or other domains. They are detailed evidence from one product, one primary failure mode and one expert annotator. Their useful conclusion is methodological: a rubric built from real product errors, validated against human labels and tested as a prompt × model pairing gave this team more decision-relevant evidence than generic templates. Another team must validate its own rubric on its own labelled cases.
Quality criteria should also encode severity. Report false positives and false negatives separately when they have different consequences. Review results by segment, not just in aggregate. Define hard release gates for unacceptable failures and softer targets for preferences. That lets a team say, for example, “no unsupported compliance claims, at least 90% field completeness, and no regression for German-language invoices,” instead of chasing one blended score.
Comparing prompts and models fairly
The unit of comparison is often the prompt × model pairing. The same instruction can be interpreted differently across models, while a prompt designed for one model may underuse another. Record both versions and judge the pairing as deployed. When you want to attribute an effect to the prompt alone, keep the model and settings fixed; when choosing a production configuration, compare named pairings under the same dataset and rubric.
Fair comparisons use identical cases, the same evaluation criteria, recorded model versions and controlled settings. Run variants close enough together that provider or dataset changes do not quietly alter conditions. Keep system prompts, retrieval context and tool access visible. Track failures at case level so an aggregate gain cannot hide a regression on the segment that matters most.
Blind review reduces preference for newer or better-known model brands. This is a practical lesson from Lovelaice’s founder experience, not an independent behavioural study: when reviewers know which response came from the fashionable model, reputation can influence how they interpret polish. Hide model identity during quality review, then reconnect the scores to cost, latency and operational constraints after the judgments are recorded.
Side-by-side review also reveals tacit requirements. Domain experts often notice that one answer prioritizes correctly, asks a safer follow-up, uses a clearer structure or avoids a phrase that could confuse users—details they did not think to put in the initial prompt. Capture these observations as candidate rubric items, then re-run the complete set. Do not simply crown the answer that inspired the most preferences.
The newest or most expensive model cannot be assumed to be best for a specific task. The Lovelaice document-extraction comparison found an 11× per-document cost range across 15 models on its documented invoice workload. That result is task-specific and pricing is time-sensitive; it supports benchmarking plausible models on the real workload, not a general ranking. The prompt-formatting comparison likewise treats Markdown, XML and JSON structure as variables to measure, not universal style rules.
Manual review before automation
Manual review is the starting point when expected outputs do not yet exist. It is not an immature workaround. Reading outputs is how a team discovers what its product actually gets wrong, which failures matter and how experts distinguish acceptable from unacceptable. Automating a generic score before doing this work creates precise-looking measurements with no proven relationship to the product decision.
Begin with a small set and ask reviewers to leave a written reason for each pass, fail or preference. Compare notes. Where reviewers disagree, clarify the rubric rather than averaging away the disagreement. Group recurring reasons into a failure taxonomy. Objective patterns—invalid JSON, missing fields, forbidden phrases or length limits—can become deterministic checks. Nuanced judgments can become a carefully written LLM judge only after enough human-labelled examples exist to validate it.
An automated evaluator earns trust by reproducing expert judgment on held-out cases, not by returning a confident score. Measure agreement, missed real errors, false alarms, reason quality and repeat-run consistency. Revalidate after changing the judge prompt or model. Keep sampled human review in the lifecycle because product behaviour, user inputs and expert standards evolve.
This workflow gives non-technical experts a concrete route through AI overwhelm. They do not need to know every model architecture. They need access to the prompt, representative cases and real outputs, plus a way to express why something works or fails. Engineering remains essential to integration and operations; experimentation lets product and domain experts contribute their unique context directly instead of treating AI as a magical component behind a ticket queue.
Measuring results
A shipping decision needs four layers of measurement: product quality, failure profile, operational performance and reliability. A single average accuracy number cannot describe all four. Keep the layers separate long enough to understand the trade-off, then make the product decision explicit.
1. Product quality
Measure the domain outcome: accuracy, completeness, usefulness, tone, refusal behaviour, citation quality or decision quality. Prefer rubric items tied to user tasks over broad impressions.
2. Failure profile
Separate false positives and false negatives. Count frequency, severity and affected segments. Inspect written reasons and examples so the team knows what to fix.
3. Operational performance
Measure latency distributions, token use and unit cost, then project realistic volume. Include retries, tool calls, retrieval and human review rather than quoting only a model’s list price.
4. Reliability
Repeat non-deterministic runs, measure verdict or output changes, and compare every material version against the baseline. Check stability at the segments and failure types that drive the decision.
The business case spans acceptable quality, cost, and latency at expected scale. A configuration with the highest quality score may make the product unusably slow. The cheapest model may require enough retries or human correction to cost more in practice. State minimum quality gates first, then compare operational trade-offs among the configurations that clear them. Do not trade away a critical safety requirement for an attractive blended average.
Confidence should be proportionate to risk. A three-case run can decide which prompt direction deserves another afternoon. It cannot justify automating a regulated decision. A larger set does not fix poor coverage, and statistical significance is not one mandatory threshold for every offline experiment. Ask whether the evidence could change the decision, whether important segments have enough coverage, whether repeated runs remain acceptable, and which unknowns are left.
Report denominators and scope beside every number. “86% accuracy” means more when the reader can see that it was six of seven expense cases in an exploratory reconstruction. “76.5% agreement” should sit beside the 34 balanced lead-qualification responses and one-product limitation. Clear scope makes evidence useful; hiding it turns a case study into marketing.
From experiment to shipping decision
The experiment is complete when the team can make and defend the stated decision. The deliverable is not a leaderboard. It is a short record connecting the selected configuration to the baseline, dataset, threshold, remaining risks and operating plan. Someone revisiting the feature months later should understand what was known at release and what requires revalidation.
01
Decision
Name the choice and the user or business consequence it addresses.
02
Selected configuration
Record prompt, model, retrieval, tools, settings and output versions.
03
Baseline and improvement
Show case-level and aggregate change against the current trusted version.
04
Dataset and scope
Describe sources, segments, exclusions, redaction and evidence limits.
05
Acceptance threshold
Preserve the release gates defined before aggregate results were reviewed.
06
Known failures
List remaining patterns, severity, affected users and accepted uncertainty.
07
Cost and latency
Project realistic volume, tail latency, retries, tokens and review effort.
08
Fallback plan
Explain escalation, human review, safe failure and rollback behaviour.
09
Monitoring plan
Name live signals, sampled review, regression cadence and owners.
10
Approvers and date
Record accountable reviewers, dissent, decision date and next review.
“Ship” can mean a limited rollout with human review rather than unrestricted automation. If a variant clears ordinary cases but retains a rare severe failure, route the risky segment to an expert or keep the existing workflow. Define rollback conditions before launch. Monitoring should capture the same quality concepts used offline so production evidence can enter the next experiment instead of living in a disconnected dashboard.
If the threshold is missed, document that too. A rejected configuration prevents the same weak approach from being rediscovered and shows what evidence would reopen the decision. Sometimes the right outcome is a narrower feature, more context, a deterministic rule around the model, or no AI at all. Experimentation earns its cost when it finds those answers before a production commitment.
Roles in the workflow
AI quality is cross-functional ownership. Product defines the user outcome and the decision the experiment must support. Domain experts define nuanced quality, acceptable exceptions and failure severity. Engineering ensures technical feasibility, integration, version control and operational measurement. Design assesses usefulness, interaction, tone, transparency and recovery. Legal or compliance defines applicable constraints in high-risk domains.
These responsibilities overlap by design. Product should not invent a compliance rubric alone; engineering should not select a model solely from a public benchmark; domain experts should not be asked to approve an unexplained aggregate score. A review session where each discipline sees the same cases creates a shared language for trade-offs. The decision record makes the ownership durable after the meeting.
Giving non-technical colleagues direct access to experimentation does not replace engineering. It reduces lossy translation. A product manager can compare outputs and sharpen the intended outcome; a claims expert can label a subtle omission; a designer can identify a recovery failure. Engineers can then implement against specific evidence and focus on system constraints that require their expertise.
Lovelaice’s experience is that teams range from an early idea to complex existing pipelines, so ownership should match maturity. At the idea stage, product and domain experts may lead a small manual comparison with engineering advising feasibility. Near release, engineering and risk owners deepen dataset controls, operational measurements, fallback behaviour and monitoring. The loop stays the same; the rigor expands with the decision.
Worked experiments and practical next steps
The four records below are first-party Lovelaice experiments. They are examples of method and documented evidence, not universal model rankings. Each record states the decision, dataset, result and limitation so you can judge whether its conclusion transfers to your context. Use the source article for full methodology before relying on a number.
B2B product operations · Lead qualification
The battle of the LLM judges
Eight judge prompts, ten models and two complete runs tested against expert labels.
- Decision
- Can generic judge templates replace a purpose-built judge validated against human labels?
- Dataset
- 34 real agent responses: 17 correct and 17 containing a real priority-tier error.
- Result
- The best purpose-built pairing reached 76.5% agreement; seven generic templates averaged 52–58%.
Variables
- Eight judge prompts
- Ten judge models
- Two identical runs
Fixed conditions
- The same 34 responses
- The same human labels
- The same output contract
Evaluation
- Agreement with human labels
- False negatives
- False positives
- Reason-level agreement
- Repeat-run stability
Metrics
- More than 5,000 verdicts
- 80 prompt × model pairings
Limitations
- One product
- One primary failure mode
- One expert annotator
Finance operations · Expense-policy decisions
Building an expense-policy AI agent
Three prompt versions and six models tested on seven expense-policy cases.
- Decision
- Which prompt structure and model combination best applies a written expense policy?
- Dataset
- Seven expense-policy test cases.
- Result
- The structured prompt on GPT-5 reached 86% accuracy (six of seven cases), compared with 43% for the basic placeholder prompt.
Variables
- Three prompt versions
- Six models
Fixed conditions
- The same seven cases
- The same underlying expense policy
Evaluation
- Decision accuracy
- Manual review of reasoning
- Manual review of policy references
- Manual review of response length
Metrics
- 126 runs
Limitations
- Seven cases
- Exploratory task reconstruction
- Not a production-readiness result
Document workflows · Policy decisions and invoice extraction
Markdown, XML or JSON prompt formatting
A comparison of prompt structure across expense-policy and invoice-extraction tasks.
- Decision
- Does structured prompt formatting improve task accuracy?
- Dataset
- The expense-policy and invoice-extraction cases documented in the canonical article.
- Result
- In the documented expense-policy comparison, GPT-5 improved from 43% to 86% with XML-structured policy context; the invoice task indicated that clear sections, rather than all-caps emphasis, produced the benefit.
Variables
- Basic placeholder
- Structured sections
- XML formatting
- All-caps emphasis
Fixed conditions
- The task within each comparison
- The source policy or document
Evaluation
- Task accuracy
- Manual comparison of formatting effects
Metrics
- Accuracy by prompt format where documented
Limitations
- Two task-specific examples
- Only documented model and dataset details may be generalized
Document processing · Structured document extraction
Document extraction cost across 15 models
Fifteen models compared on the same extraction task for per-document cost.
- Decision
- What is the task-specific model-cost range for the same extraction workload?
- Dataset
- The same set of standard-length invoices used for the documented cost comparison.
- Result
- Across the same extraction task, 15 models ranged from around $0.001 to $0.011 per standard-length invoice—an 11× cost gap.
Variables
- Fifteen models
Fixed conditions
- The same extraction task
- The same invoice set
Evaluation
- Cost per document
Metrics
- Approximately $0.001–$0.011 per standard-length invoice
- 11× cost gap
Limitations
- One extraction task
- Model pricing and versions are time-sensitive
Frequently asked questions
These concise answers cover the decisions teams most often face when starting or formalising AI experimentation. Each answer uses the same definitions and thresholds as the guide above.
What is AI experimentation?
AI experimentation is the structured process of testing prompts, models, and other AI configurations against the same representative dataset and product-specific quality criteria. It helps a product team understand what works, why it works, what it costs, and which failures remain before making a production decision.
Is AI experimentation the same as AI evaluation?
No. Experimentation is the controlled process that compares alternatives and produces evidence. Evaluation is the method used to judge the outputs inside that process. Evaluation can happen without a comparison, but an AI experiment cannot support a decision unless its outputs are evaluated against clear criteria.
How is AI experimentation different from A/B testing?
AI experimentation usually examines output quality on controlled inputs before release. A/B testing measures how real users behave after variants are released. Teams often need both: first establish that an AI variant meets the quality and safety threshold offline, then test whether it improves user behaviour online.
What is prompt experimentation?
Prompt experimentation compares prompt versions on the same test cases, model settings, and evaluation criteria. The goal is not to choose the most persuasive-looking answer from one example. It is to measure whether a specific instruction change improves the intended quality without creating regressions elsewhere in the dataset.
How many test cases should an AI experiment include?
Start with three to five realistic cases to learn how the feature behaves. Expand to roughly 20–50 carefully chosen examples to identify recurring failures and establish an initial baseline. Higher-risk shipping decisions need broader validation, repeated runs, and coverage of important segments and edge cases.
How many models should a team compare?
Compare enough models to test a meaningful range of families, sizes, costs, and latency profiles. There is no universal number. The selection should answer the product decision and include plausible production options, not every model available or only the newest model in each family.
Should teams test prompts or models first?
Treat the prompt and model as a pairing because the same prompt can behave differently across models. For a clear experiment, change one decision variable at a time while keeping the dataset and evaluation criteria fixed, then validate the winning pairing against the baseline.
Can non-technical experts run AI experiments?
Yes. Product managers and domain experts are often best placed to define what a useful, correct, or safe output looks like. Engineering remains essential for integration and operational constraints, while the experiment gives experts a direct way to contribute their judgment without translating every observation through a technical ticket.
How do you measure subjective AI outputs?
Write a rubric in the language domain experts use, compare outputs side by side where helpful, and record why each answer passes or fails. Those written reasons reveal recurring failure patterns and can later become deterministic checks or a calibrated LLM judge validated against human labels.
When is an AI experiment reliable enough to ship?
It is reliable enough for the stated decision when it meets a threshold defined before the results were reviewed, covers the important user segments and failure risks, remains acceptable on repeated runs, and has documented limitations, fallback behaviour, and a plan for monitoring production performance.
What should be documented after an AI experiment?
Record the decision, selected prompt and model versions, dataset and exclusions, evaluation rubric, baseline, results, failure patterns, limitations, cost, latency, fallback plan, monitoring plan, approvers, and date. This makes later comparisons reproducible and keeps the shipping decision from becoming institutional memory.
How often should an experiment be repeated?
Repeat the relevant evaluation whenever a material prompt, model, retrieval source, tool, dataset, or workflow changes. Also repeat non-deterministic comparisons when a single run could change the decision. Every material version should be measured against the same baseline before release.

