api-messaging-webhooks SKILL.md skillA
api-messaging-webhooks from agents-inc/skills is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add agents-inc/skills/api-messaging-webhooks@git:20261016.afd0e14Pins git:20261016.afd0e14 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- agents-inc/skills
- Path
src/skills/api-messaging-webhooks/SKILL.md- Versions recorded
- 2
- Latest version
- git:20261016.afd0e14, committed Oct 16, 2026
- First version recorded
- Jul 9, 2026
- Size
- 15,712 bytes
- Repository stars
- 26
- License
- MIT
Webhook patterns — receiving, sending, signature verification, and retry logic.
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
# Webhook Patterns > **Quick Guide:** Verify signatures with HMAC-SHA256 using `crypto.createHmac` + `crypto.timingSafeEqual` on the **raw body bytes** -- never parsed JSON. Enforce idempotency by storing processed webhook IDs. Protect against replay attacks with timestamp validation. Return 200 immediately, process asynchronously. When sending, use exponential backoff with jitter and move exhausted retries to a dead letter queue. --- <critical_requirements> ## CRITICAL: Before Using This Skill **(You MUST verify signatures against the RAW request body -- never parsed/re-serialized JSON)** **(You MUST use `crypto.timingSafeEqual` for signature comparison -- never `===` which leaks timing information)** **(You MUST return 2xx immediately and process webhooks asynchronously -- synchronous processing causes timeouts and duplicate deliveries)** **(You MUST enforce idempotency by checking a stored webhook ID before processing -- retries WILL send the same event multiple times)** </critical_requirements> --- …
Read the whole file at its exact version.
How to install
mdr add agents-inc/skills/api-messaging-webhooks@sha256:e7372d69c792ea8fThe line at the top of this page pins the label git:20261016.afd0e14, 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_wds36fzsvwq2rfrs)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 2 versions of this file, between Jul 9, 2026 and Oct 16, 2026, about one every 99 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261016.afd0e14 latest | 2026-10-16 | afd0e14 | 15,712 B | A | view · diff |
| git:20260709.a28d77d | 2026-07-09 | a28d77d | 15,911 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 (15712 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
agents-inc/skills · 26 stars · license MIT · pushed 2026-10-27 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_wds36fzsvwq2rfrs GET https://markdownregistry.com/api/v1/resolve?ref=agents-inc/skills/api-messaging-webhooks GET https://markdownregistry.com/api/v1/blob/e7372d69c792ea8f1da2f3c7a1e0834cf9988f81fb2bb5904f614c884d8d916b
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.