Agent skill · software engineering · jeremylongshore
alchemy-webhooks-events
Operate Alchemy Notify webhooks with raw-body HMAC verification, idempotent intake, durable processing, and safe lifecycle changes. Use when implementing or repairing blockchain event delivery. Trigger with "Alchemy webhook", "Alchemy Notify", or "verify X-Alchemy-Signature".
Why this skill is useful
Provides specific commands and code snippets for implementing Alchemy Notify webhooks that are not widely known.
What it needs
Requires curl installed locally. Requires alchemy account access. About 3k tokens when loaded. Last updated 2026-08-07. 2,604 stars on the source repository.
What this skill does
Alchemy Notify Webhook Operations Overview Operate Alchemy Notify webhooks with raw-body HMAC verification, idempotent intake, durable processing, and safe lifecycle changes. This workflow produces a reviewable artifact and negative-path evidence before any live side effect. Prerequisites Current first-party Alchemy documentation for the selected product, chain, feature, client, authentication method, limit, and lifecycle. Named product, application, security, data/privacy, budget, release, and operations owners appropriate to the requested scope. Synthetic or approved non-production fixtures, a credential canary, explicit success criteria, and a tested rollback boundary. Current Contract Alchemy signs the exact raw request body with HMAC-SHA256 using the webhook's signing key and sends the digest in X-Alchemy-Signature. Notify management uses its documented auth token, not the signing key. Current docs describe automatic retries/backoff and ordered first-time delivery; consumers still need idempotency because duplicate processing and application retries remain possible. Authentication Keep the per-webhook signing key and Notify management token in separate managed secrets. The receiver may read the signing key only for verification; it may not create, update, or delete webhook registrations. Instructions 1. Select the current webhook type and network from first-party support, define event semantics, confirmation policy, callback SLO, and data retention. 2. Create or modify the registration only through an approved management path; record webhook ID, redacted filter, owner, signing-key version, and rollback configuration. 3. Capture the raw request bytes before JSON parsing, compute HMAC-SHA256, and compare decoded equal-length values with a timing-safe function. 4. Persist the webhook and event identifiers atomically before acknowledging; enqueue work and return success without blocking on downstream side effects. 5. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills jeremylongshore/alchemy-webhooks-events