How do I install the Surface skill?

Run npx skillmds@latest add prebid/surface in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Surface safe to use?

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Which AI agents work with Surface?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Surface free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Surface?

prebid (@prebid) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Surface by prebid — Agent Skill

Name: Surface
Author: prebid

Surface

Map the complete test surface for domain entities by cross-referencing test-obligations with existing tests. Produces one canonical test module per entity with real tests + skip stubs for gaps. Every obligation maps to exactly one test. Run this before /remediate.

prebid e07aeef 3.0 KB Updated Sep 17, 2026

File contents

Entity Test Surface Mapping

Create canonical test suites per domain entity by mapping all test obligations to real tests or stubs. This gives complete visibility into what's tested and what's missing.

Args

/surface <entity-name-1> [entity-name-2] ...

Entity names (space-separated). Each gets a test file at tests/unit/test_{entity_name}.py (hyphens → underscores).

Entity → Obligations Mapping

Entity	Primary Obligations	Output File
product	UC-001	test_product.py
media-buy	UC-002, UC-003	test_media_buy.py
delivery	UC-004	test_delivery.py
creative-formats	UC-005	test_creative_formats.py
creative	BR-UC-006	test_creative.py
properties	BR-UC-007	test_properties.py
audience-signals	BR-UC-008	test_audience_signals.py
performance	BR-UC-009	test_performance.py
capabilities	BR-UC-010	test_capabilities.py
pricing-option	business-rules, constraints	test_pricing_option.py
transport-boundary	#1050/#1066 principles	test_transport_boundary.py

All entities also check cross-cutting files: business-rules.md, constraints.md.

What You Get

For each entity, a test module containing:

Real tests: Ported from existing (possibly scattered) test files
Skip stubs: @pytest.mark.skip(reason="STUB: [obligation-ID]") for every gap
Obligation traceability: Each test/stub references its obligation ID

Open test_creative.py → see 89 test names → 30 real, 59 stubs → know exactly what's missing.

Protocol

Step 1: Cook the molecule

python3 .claude/scripts/cook_formula.py \
  --formula .claude/formulas/entity-test-surface.yaml \
  --var "ENTITY_NAMES={all_args}" \
  --epic-title "Surface: {all_args}"

Dry run first (recommended):

python3 .claude/scripts/cook_formula.py \
  --formula .claude/formulas/entity-test-surface.yaml \
  --var "ENTITY_NAMES={all_args}" \
  --epic-title "Surface: {all_args}" \
  --dry-run

Step 2: Walk the molecule

bd ready → bd show <atom-id> → execute → bd close <atom-id> → repeat

Each entity goes through: gather-obligations → audit-existing → review → triage → generate-suite → verify → commit.

Step 3: Done when all atoms closed

All entity suites committed. Coverage summary generated.

Naming Rules

Test names describe behavior, not bugs:

test_create_media_buy_rejects_missing_brand (behavior)
NOT: test_bug_fix_123 or test_v2_compat (incident-driven)

---name: surfacedescription: Map the complete test surface for domain entities by cross-referencing test-obligations with existing tests. Produces one canonical test module per entity with real tests + skip stubs for gaps. Every obligation maps to exactly one test. Run this before /remediate.---# Entity Test Surface MappingCreate canonical test suites per domain entity by mapping all test obligationsto real tests or stubs. This gives complete visibility into what's tested andwhat's missing.## Args```/surface <entity-name-1> [entity-name-2] ...```Entity names (space-separated). Each gets a test file at`tests/unit/test_{entity_name}.py` (hyphens → underscores).## Entity → Obligations Mapping| Entity | Primary Obligations | Output File ||--------|-------------------|-------------|| product | UC-001 | test_product.py || media-buy | UC-002, UC-003 | test_media_buy.py || delivery | UC-004 | test_delivery.py || creative-formats | UC-005 | test_creative_formats.py || creative | BR-UC-006 | test_creative.py || properties | BR-UC-007 | test_properties.py || audience-signals | BR-UC-008 | test_audience_signals.py || performance | BR-UC-009 | test_performance.py || capabilities | BR-UC-010 | test_capabilities.py || pricing-option | business-rules, constraints | test_pricing_option.py || transport-boundary | #1050/#1066 principles | test_transport_boundary.py |All entities also check cross-cutting files: `business-rules.md`, `constraints.md`.## What You GetFor each entity, a test module containing:- **Real tests**: Ported from existing (possibly scattered) test files- **Skip stubs**: `@pytest.mark.skip(reason="STUB: [obligation-ID]")` for every gap- **Obligation traceability**: Each test/stub references its obligation IDOpen `test_creative.py` → see 89 test names → 30 real, 59 stubs → know exactly what's missing.## Protocol### Step 1: Cook the molecule```bashpython3 .claude/scripts/cook_formula.py \ --formula .claude/formulas/entity-test-surface.yaml \ --var "ENTITY_NAMES={all_args}" \ --epic-title "Surface: {all_args}"```**Dry run first** (recommended):```bashpython3 .claude/scripts/cook_formula.py \ --formula .claude/formulas/entity-test-surface.yaml \ --var "ENTITY_NAMES={all_args}" \ --epic-title "Surface: {all_args}" \ --dry-run```### Step 2: Walk the molecule```bd ready → bd show <atom-id> → execute → bd close <atom-id> → repeat```Each entity goes through: gather-obligations → audit-existing → review → triage → generate-suite → verify → commit.### Step 3: Done when all atoms closedAll entity suites committed. Coverage summary generated.## Naming RulesTest names describe **behavior**, not bugs:- `test_create_media_buy_rejects_missing_brand` (behavior)- NOT: `test_bug_fix_123` or `test_v2_compat` (incident-driven)## See Also- `/remediate` — Fill the stubs this skill creates- `/guard` — Structural guards that prevent new violations- `/mol-execute` — Execute individual beads tasks (now entity-suite-aware)

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