decision-model-authoring

name	decision-model-authoring
description	Author and validate decision models from PNS decision points using DMN-aligned rule tables. Use this skill when the PNS contains three or more gateway decision points that warrant a structured decision table; when the user asks to document business rules as decision logic, build a DMN table, or make decision criteria explicit. This is a recommended extension skill triggered automatically when visual-process-modeling identifies three or more gateways. Produces a decision-model YAML and a human-readable DMN rule table.
license	MIT
homepage	https://github.com/overkillhill/mermaid-diagram-bpmn/tree/main/skills/decision-model-authoring
repository	https://github.com/overkillhill/mermaid-diagram-bpmn
metadata	{"bp_skill_version":"0.3.0","status":"recommended-extension","version":"0.1.0","author":"OverKill Hill P³","project":"BP-SKILL: Business Process Agent Skill Suite","category":"process-documentation","standards_refs":["OMG DMN 1.4 (Decision Model and Notation)","BABOK v3 §10.11 (Business Rules Analysis)","BPM CBOK v4 §5.4 (Decision Modelling)"],"produces":"decision-model.yaml, dmn-table.md","consumes":"pns.yaml","depends_on":["process-narrative-authoring"],"tags":"decision-model, DMN, business-rules, decision-table, gateways, rule-table, process-logic","triggers":["decision table","DMN model","business rules table","document decision logic","decision model","rule table","three or more gateways","make the decision criteria explicit"]}

Purpose

Transform PNS decision_points into structured DMN-aligned decision models. Each decision point becomes a decision table with explicit input conditions, output values, and the business rule governing the routing logic.

---

When to use this skill

• PNS has ≥3 decision_points — this is the mandatory trigger condition
• User needs a decision table to communicate routing logic to implementers
• Business rules are complex enough that prose descriptions are insufficient
• Preparing a decision catalog as part of governance documentation

When NOT to use this skill

• PNS has fewer than 3 decision_points — inline the logic in the PNS decision_points[] section
• Decision logic is trivially binary (yes/no) with no business rule — document in business_rules[] instead
• Do not model decisions before the PNS is validated (score ≥ 75)

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DMN Table Structure

Each decision table entry has:

Field	Description
decision_id	Stable identifier matching pns.decision_points[].id
decision_name	Human-readable label
activity_id	The PNS activity where this decision occurs
hit_policy	U (Unique) | F (First) | A (Any) | C (Collect)
inputs[]	Each input: name, type (string|number|boolean), values[]
outputs[]	Each output: name, type, values[]
rules[]	Each rule: id, conditions{}, output{}, annotation

---

Authoring Workflow

Step 1 — Extract decision points

Read pns.decision_points[] and group by the activity_id where they occur.

Step 2 — Identify inputs and outputs

For each decision:

• Inputs — the data values or conditions being evaluated (from criteria)
• Outputs — the possible routing outcomes (from outcomes[].label)

Step 3 — Select hit policy

Situation	Hit policy
Exactly one rule fires per input combination	U (Unique)
Rules are ordered; first match wins	F (First)
Multiple rules can fire but give the same output	A (Any)
Multiple rules can fire and outputs are aggregated	C (Collect)

Step 4 — Write rules

For each combination of input values, specify the output. Mark any unhandled combination as FAIL — do not silently default.

Step 5 — Validate traceability

Every decision_id must match a pns.decision_points[].id. Every output value must match a pns.decision_points[].outcomes[].label.

---

DMN Table Markdown Format

## Decision: Approve PO Request (gw-001)

Hit policy: **U** (Unique)

| Amount | Requester Level | → Outcome |
|---|---|---|
| ≤ 1000 | any | Auto-approve |
| > 1000 | manager | Manual review |
| > 1000 | staff | Escalate to Director |
| > 10000 | any | Board approval required |

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Handoff Instruction

Pass decision-model.yaml and dmn-table.md to publication-and-handoff-packaging for bundle assembly.

Use decision_id values as gateway label annotations in the bpmn-beta.mmd diagram.

---

References

Load on demand:

• references/dmn-modeling-rules.md — hit policy selection rules, input/output type definitions, and traceability requirements

Scripts

• scripts/validate-decision-model.mjs — validates decision model structure, hit policy completeness, and PNS traceability

Assets

• assets/fixtures/decision-model-example.yaml — canonical decision model for purchase-approval gateway logic