Conciseness

Core sections are code-first and efficient, but the "Common Event Types" table and "Top-Level Payload Structure" duplicate content already in references/overview.md, and roughly 20 lines of "Related Skills" promotional links (11 external repos) pad the token budget. Mostly efficient but could be tightened — the level-3 anchor fits better than level 4 because the duplication and promotional footer go beyond minor trimming.

Actionability

Two complete, copy-paste-ready handlers (Express with discord-interactions and FastAPI with PyNaCl) covering raw-body capture, header checks, Ed25519 verification, PING 204 response, and event dispatch, plus concrete env-var and tunnel commands ("npx hookdeck-cli listen 3000 discord --path /webhooks/discord"). Fully executable and covering the common cases — level 5.

Workflow Clarity

The critical ordering (verify signature before parsing, respond 204 to PING) is explicit in both code examples, and the PING section states that "Endpoint registration fails until your handler does this correctly" — a real checkpoint. However the end-to-end setup sequence (public key → handler → tunnel → portal registration → PING validation) is implicit, scattered across sections rather than sequenced; level 4 with minor validation gaps.

Progressive Disclosure

Three real, clearly labeled, one-level-deep reference files (references/overview.md, setup.md, verification.md) are well signaled in a Reference Materials section with descriptions. Minor gaps: the "examples/express/", "examples/nextjs/", and "examples/fastapi/" links point to directories that do not exist in the bundle, and the event table and payload structure duplicate reference content inline. Good structure overall — level 4 rather than 5 because of the broken example paths and inline duplication.

Specificity

Lists multiple concrete actions — "Receive and verify Discord webhook events", "debugging Ed25519 signature verification", "handling PING endpoint validation", "processing events like APPLICATION_AUTHORIZED, ENTITLEMENT_CREATE, or LOBBY_MESSAGE_CREATE" — with comprehensive coverage of the skill's domain. It exceeds the level-4 anchor because there are no minor gaps in the action inventory for this domain.

Completeness

Explicitly answers both questions: the "what" is "Receive and verify Discord webhook events" (third person) and the "when" is an explicit "Use when setting up Discord webhook handlers, debugging Ed25519 signature verification, handling PING endpoint validation, or processing events..." with concrete trigger phrases. Matches the level-5 anchor exactly.

Trigger Term Quality

Good natural keyword coverage ("Discord webhook handlers", "signature verification", "PING endpoint validation", concrete event names), but a few natural user phrasings are missing — e.g. the "invalid request signature" error the body explicitly targets, generic "Discord events" phrasing, or the Interactions-endpoint synonym for the same signing scheme. Not level 5 because synonym/variation coverage is not comprehensive.

Distinctiveness Conflict Risk

"Discord" plus provider-specific event names (APPLICATION_AUTHORIZED, ENTITLEMENT_CREATE) form a clear niche with distinct triggers; it would not fire for sibling provider webhook skills (Stripe, Shopify, GitHub). Minimal conflict risk — level 5.