cfn-behavior-validator SKILL.md skillA
cfn-behavior-validator from pantheon-org/tekhne is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add pantheon-org/tekhne/cfn-behavior-validator@git:20260923.7852cb4Pins git:20260923.7852cb4 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- pantheon-org/tekhne
- Path
skills/infrastructure/cfn/behavior-validator/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260923.7852cb4, committed Sep 23, 2026
- First version recorded
- Mar 3, 2026
- Size
- 9,821 bytes
- Repository stars
- 10
- License
- MIT
Creates test stacks, analyzes CloudFormation events, compares actual vs documented update behavior, then confirms whether a resource property change triggers replacement rather than an in-place update. Use when: testing if a CFN property change causes resource replacement; investigating stack update behavior, "Update requires" documentation accuracy; validating whether a workaround (e.g. hash-based logical IDs) is actually necessary; questioning UpdateRequiresReplacement behavior for immutable…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# CloudFormation Resource Update Behavior Validator ## Purpose Empirically validate how CloudFormation handles specific resource property changes by deploying a controlled test stack, making a targeted change, and observing actual CFN events — then deciding whether workarounds are justified. ## Mindset Documentation is a hypothesis, not a fact: the "Update requires" value is maintained by hand and drifts from actual resource-provider behavior, and it never encodes interaction effects between properties on the same resource. Treat every rating as unverified until real CFN events back it up — never carry a workaround, or its removal, into production on a documentation read alone. A change CloudFormation applies in-place can still be disruptive underneath: a Lambda VPC change is rated "some interruption" but always forces ENI churn that shows up only in the `ELASTIC_NETWORK_INTERFACE` events, never on the Lambda resource's own status line. **Decision framework:** 1. **State the hypothesis before touching a stack** — a test with no falsifiable prediction is not a test. …
Read the whole file at its exact version.
How to install
mdr add pantheon-org/tekhne/cfn-behavior-validator@sha256:5bf4fc5962a1e5c3The line at the top of this page pins the label git:20260923.7852cb4, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_pdrrhcjcgsa54hwt)
1 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Mar 3, 2026 and Sep 23, 2026, about one every 102 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260923.7852cb4 latest | 2026-09-23 | 7852cb4 | 9,821 B | A | view · diff |
| git:20260316.2d4c8cf | 2026-03-16 | 2d4c8cf | 5,948 B | A | view · diff |
| git:20260303.e1f9610 | 2026-03-03 | e1f9610 | 4,230 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (9821 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
pantheon-org/tekhne · 10 stars · license MIT · pushed 2026-10-21 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_pdrrhcjcgsa54hwt GET https://markdownregistry.com/api/v1/resolve?ref=pantheon-org/tekhne/cfn-behavior-validator GET https://markdownregistry.com/api/v1/blob/5bf4fc5962a1e5c3a0fc283d87afb121812c25fb2f8c3edea35262e994f07e79
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.