derive-tests

derive-tests is a skill for Claude Code, Codex from prebid/salesagent. It costs 50 tokens per session (4,289 once invoked), scanned A, original, Apache-2.0.

Derive obligation tests using the test harness. First checks for harness availability, then generates compact tests using domain-specific test environments. Hard gate: no harness -> no tests (stops immediately). Replaces obligation-test for harness-enabled domains.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/prebid/salesagent/derive-tests
Any agent
npx skills add prebid/salesagent --skill derive-tests
Clone the repo
git clone --depth 1 https://github.com/prebid/salesagent

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for derive-tests

README.md
[![agentmods](https://agentmods.dev/badge/skills/prebid/salesagent/derive-tests.svg)](https://agentmods.dev/skills/prebid/salesagent/derive-tests)
Your own site
<a href="https://agentmods.dev/skills/prebid/salesagent/derive-tests"><img src="https://agentmods.dev/badge/skills/prebid/salesagent/derive-tests.svg" alt="Measured on agentmods" height="20"></a>
Per session 50 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,289 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00050 $0.04289
Opus 5 $0.00025 $0.02145
Sonnet 5 $0.00010 $0.00858
Haiku 4.5 $0.00005 $0.00429

Measured 3d ago against content hash 794a44ffdad1, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

derive-tests scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

env.mock["post"] # requests.post mock
.claude/skills/derive-tests/SKILL.md · 512 lines

How it starts

The opening of the file, as written. The whole thing — 512 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Harness-Based Obligation Test Derivation

Write one behavioral test per obligation using the test harness (tests/harness/). Tests use domain-specific test environments instead of inline @patch decorators, producing 10-15 line tests instead of 40-50 line tests.

Args

/derive-tests UC-004-MAIN-01 UC-004-MAIN-02
/derive-tests UC-004 --count 10
/derive-tests UC-001-MAIN --count 15

Direct IDs: Space-separated obligation IDs. Prefix mode: Auto-selects uncovered obligations matching the prefix.

Available Harness Environments

Domain Env Class Tests Production Function
Delivery poll DeliveryPollEnv test_delivery_poll_behavioral.py _get_media_buy_delivery_impl
Webhook delivery WebhookEnv test_delivery_webhook_behavioral.py deliver_webhook_with_retry
Circuit breaker CircuitBreakerEnv test_delivery_service_behavioral.py WebhookDeliveryService, CircuitBreaker
Creative sync CreativeSyncEnv test_creative_sync_behavioral.py _sync_creatives_impl
Creative list CreativeListEnv test_creative_list_behavioral.py _list_creatives_impl
Creative formats CreativeFormatsEnv test_creative_formats_behavioral.py _list_creative_formats_impl

Multi-transport support: Creative envs support call_via(transport) dispatch across IMPL, A2A, and REST transports. See Multi-Transport Pattern.

Protocol

Step 0: Resolve obligation IDs

If args look like a prefix (no trailing -NN sequence number):

python3 -c "
import json
al = json.loads(open('tests/unit/obligation_coverage_allowlist.json').read())
matches = sorted(oid for oid in al if oid.startswith('{prefix}'))
print(' '.join(matches[:N]))
print(f'Total matching: {len(matches)}, selected: {min(N, len(matches))}')
"

Step 1: Harness gate (HARD STOP)

Check if a harness exists for the target domain:

ls tests/harness/*.py

Read the full file on GitHub · 512 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 512 lines · 50 tokens per session scan A 794a44ffdad1

Subscribe to this mod's changes

derive-tests is a skill published in the GitHub repository prebid/salesagent (37 stars, last pushed today), licensed Apache-2.0. It adds 50 tokens to every session and 4,289 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-01.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

brainstorming

You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.

obra/superpowers · 37 tokens

auto-perf-optimize

Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.

microsoft/vscode · 62 tokens

chat-perf

Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.

microsoft/vscode · 51 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens