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The user-personas-behavior skill produces the document that keeps a project honest about who it is actually being built for — and how anyone will know, after launch, whether it worked. Technical documents in the Engineering Docs pipeline specify what the system does; this skill specifies who needs it to do that and why, using the Jobs-to-Be-Done framework rather than shallow demographic labels. It then defines the success metrics and the concrete analytics events required to measure them, so “is this working?” has a data-backed answer instead of an opinion after launch.

At a Glance

Best For

  • Defining target users and their goals before or alongside writing a technical specification
  • Resolving disagreement about who a feature is really for and what problem it solves for them
  • Defining the success metrics and KPIs a project will be judged against post-launch
  • Specifying exactly what analytics events must be instrumented to measure those metrics

How to Invoke It

user-personas-behavior is automatically invoked as Phase 0.6 when you use using-engineering-docs. Invoke it directly when you already have a business concept and want to produce or update the personas document alone.

Example Scenarios

Expense-reporting tool

“Define the target user personas and jobs-to-be-done for our new expense-reporting tool.”

Onboarding redesign

“What should we track to know if our onboarding redesign is actually working?”

Marketplace seller experience

“Write the user behavior and success metrics document for our marketplace’s seller-side experience.”

Interview Process

The skill loads all prior documents first, then asks a maximum of 3 focused questions about information that isn’t already captured. Context loading: Before asking any questions, the skill reads all prior documents in .engineering-docs/ and extracts target users, value proposition, and problem statement. Only information that is genuinely missing triggers a question. Skill-specific questions:
  1. Distinct user types — Are there meaningfully different types of users with different goals, or is this one persona with varying context?
  2. Business success definition — What does the business need to see happen for this to be considered a win — retention, revenue, reduced support load, something else?
  3. Existing measurement — Is there analytics tooling already in place, or does this plan need to specify what to stand up?
All questions are delivered one at a time via tool calls with multiple-choice options and an “I don’t know, you decide” escape hatch.

Key Concepts

Personas are defined by the job they are hiring the product to do — not by age, gender, job title, or other demographic labels. Demographics rarely change what gets built and can bake in assumptions that don’t hold.JTBD format: “When [situation], I want to [motivation], so I can [expected outcome].”Not useful: “Priya, 34, marketing manager.”Useful: “A user who needs to approve or reject an expense report in under 60 seconds from a phone, several times a day.”The second version tells an implementer exactly what to build and how to judge whether they succeeded.
Describe usage patterns that affect design decisions:
  • Frequency of use — daily vs. rare
  • Context of use — mobile/on-the-go vs. desk
  • Domain proficiency — novice vs. power user
  • Friction tolerance — how much delay is acceptable for this specific task
These directly inform UI and flow decisions; biographical detail generally doesn’t.
Not every user matters equally to every decision. Name the primary persona(s) whose needs win in a trade-off, and secondary personas whose needs matter but yield when in conflict.Undeclared priority between personas causes design debates to stall indefinitely. The document must declare an explicit priority ranking with rationale.
  • Leading indicators: Observable quickly, predict future outcomes (e.g., % of users completing onboarding step 1). Let you course-correct before lagging indicators are even measurable.
  • Lagging indicators: The actual business outcome, observable only after time passes (e.g., 90-day retention, revenue).
A good metrics set has both. Every persona needs at least one leading and one lagging indicator with a specific numeric target.
All analytics events follow a strict snake_case verb_noun convention:
  • Format: {verb}_{noun} — e.g., signup_started, report_exported, payment_failed
  • Verbs: created, updated, deleted, viewed, started, completed, failed, clicked, submitted
  • Nouns: the entity or action affected — user, report, payment, onboarding_step
  • Properties: same convention — time_to_complete_sec, error_code, source_channel
  • Never use camelCase, PascalCase, or ambiguous names like trackEvent1
Every event needs a precise name, the exact trigger condition, the properties captured, and which metric it feeds — this becomes the developer’s instrumentation checklist.
Explicitly defining who this product is not designed to serve prevents scope creep and helps the team say “no” to feature requests that would dilute the product for its core users.For each negative persona:
  • State who they are and why they are not a target
  • Identify what they would want that conflicts with primary persona needs
  • Note the risk if this persona is accidentally prioritized
At least one persona must include an accessibility dimension to ensure a11y is designed in, not bolted on:
  • Visual impairment — uses screen readers; needs semantic HTML, alt text, ARIA labels
  • Motor impairment — uses keyboard-only or switch navigation; needs large touch targets
  • Cognitive load — needs clear language, predictable patterns, minimal cognitive overhead
  • Situational impairment — using the product in bright sunlight, noisy environment, or one-handed
Accessibility personas influence flow design (keyboard tab order, focus management, error recovery) — not just visual design.

The 6-Phase Generation Process

1

Phase 1: Socratic Clarification (Mandatory Interview)

Load all prior documents. Extract already-known user information. Ask at most 3 questions about distinct user types, business success definition, and existing measurement tooling.
2

Phase 2: Persona Definition (60–90 min)

Define each persona using JTBD framing and behavior/context, not demographics. Mark primary vs. secondary. Include at least one accessibility persona. Define negative personas.
3

Phase 3: Journey and Pain Point Mapping (40–60 min)

For each primary persona, map the end-to-end journey across all touchpoints: discovery, first use, repeated use, and eventual advocacy or churn. Capture emotional state, moments of delight, moments of friction, and handoffs between channels or sessions.
4

Phase 4: Success Metrics (40–60 min)

Define leading and lagging indicators per persona and for the business overall. Every metric needs a specific numeric target and a measurement methodology — not just “track engagement.”
5

Phase 5: Analytics and Event Tracking Plan (60 min)

For each metric, specify the exact event name, trigger condition, properties captured, and which metric it feeds. Include implementation notes: analytics platform choice, identity resolution, event delivery (client-side vs. server-side), data warehouse, and consent/privacy handling.
6

Phase 6: Revision (After User Review)

Apply requested changes, check for conflicts with prior documents, re-run consistency check, update metadata, and confirm with user.

What It Produces

The output document (3-user-personas.md) covers 9 sections:
  1. Overview — 2–3 sentences on what product/feature this covers and what decisions this document informs
  2. Personas — one block per persona: JTBD statement, behavior/context table (frequency, context, proficiency, friction tolerance), current alternative, pain point addressed, accessibility needs
  3. Negative / Exclusion Personas — who the product is NOT for; what they’d want that conflicts; risk if prioritized
  4. User Journey Map — per primary persona: stage, user action, emotional state, touchpoint, friction/delight
  5. Persona Priority — explicit ranking with rationale for tie-breaking design decisions
  6. Success Metrics — leading indicators table (metric, target, what it measures, measurement methodology) + lagging indicators table (metric, target, measured at, measurement methodology)
  7. Analytics and Event Tracking Plan — event name, fires when, properties captured, feeds which metric; implementation notes on platform, identity resolution, delivery, data warehouse, and consent
  8. Persona Validation Plan — per persona: validation method, timeline, invalidation criteria, revision trigger
  9. Open Questions — unresolved items with owner

Persona Validation Plan

Personas are hypotheses, not facts. For each persona the document defines:

Common Gotchas

Defining personas by demographics instead of behavior. “Sarah, 28, marketing manager” tells an implementer nothing actionable. Define every persona by the job they are hiring the product to do, their usage context, and their friction tolerance.
Listing only lagging indicators. Revenue and retention take weeks or months to measure. Without leading indicators, you cannot course-correct until it is too late. Every persona needs both.
Writing analytics events that are too vague to instrument. “Track user engagement” is not an event specification. Every event needs a precise name, exact trigger condition, properties captured, and which metric it feeds.
Not declaring persona priority for tie-breaking. When two personas have conflicting needs, an undeclared priority means the design debate stalls indefinitely. Always rank personas so that trade-off decisions have a deterministic resolution.

Handoff

Reads From

  • 1-business-plan.md — target users, value proposition, problem statement

Feeds Into

  • ux-flow-specification — persona goals, journey context, friction tolerance
  • technical-specification — user-driven functional requirements, success metrics as NFRs
  • design-system-specification — persona context and usage patterns for UI decisions

Quality Gate

Before marking this document as final, verify:
  • Every persona is defined by a job-to-be-done with behavior and context, not just demographic labels
  • Each persona has both leading and lagging success metrics with specific numeric targets
  • The analytics event tracking plan specifies exact event names, trigger conditions, properties, and which metric each event feeds
  • Persona priority ranking is declared with rationale, providing a deterministic tie-breaker for design decisions
  • At least one validation criterion is defined for each persona explaining how post-launch data will confirm or revise the hypothesis