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.
npx agentmods add rules/webhook-co/webhook/datagit clone --depth 1 https://github.com/webhook-co/webhookWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.00410 |
| Opus 5 | $0.00000 | $0.00205 |
| Sonnet 5 | $0.00000 | $0.00082 |
| Haiku 4.5 | $0.00000 | $0.00041 |
Grade A, and why
data scanned grade A with 0 findings 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 yesterday.
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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Data, migrations & metering
PII / PHI handling
- Treat webhook payloads as untrusted and potentially sensitive (PII/PHI). Store raw bodies in R2 (batched), not Postgres — Postgres holds metadata, config, and dedup/idempotency keys only.
- Scrub PII/PHI from logs and traces. Never log full payloads, headers with secrets, tokens, or tenant identifiers. Redact at the boundary.
- Tenant isolation via Postgres RLS is mandatory — every tenant-scoped table enforces row-level security. Never rely on app-layer filtering alone.
- Encryption at rest and in transit; honor region pinning for region-constrained records.
Safe migrations
- Migrations are forward-only and reversible in practice: ship expand → backfill → contract in separate steps. No destructive change (drop column/table, type narrowing) in the same release that starts using the new shape.
- Migrations must be idempotent and safe to re-run; large backfills run in batches, off the hot path. Never lock a hot table for long.
- Preserve the append-only, hash-chained audit log — never rewrite or delete audit history in a migration.
- Every migration has a tested rollback path before it reaches production.
Metering integrity
- Event metering is single-dimension (events) and must be accurate and idempotent — count each event once, dedup by id, and make counting replay-safe.
- Never introduce hidden per-step or multi-dimension counters. Metering integrity is a correctness concern. (No prices, tiers, or cost figures belong in this repo.)
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.
- yesterday First seen · 36 lines · 410 tokens per session scan A b279d273e3d0
data is a cursor rule published in the GitHub repository webhook-co/webhook (0 stars, last pushed 6d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 410 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other cursor rules, from other repositories
docs
All documentation files use MDX format with a specific structure.
type-inference
Derive TypeScript types from Zod schemas - no hand-written interfaces for wire shapes.
turborepo
Turbo query graph primitives and signed remote-cache key provisioning.
workers-cache
Workers Cache - Cache-Control, gateway exports cache off, RPC vs fetch.
boundaries
Package dependency boundaries - tag map and enforced invariants.
react
React 19 SPA invariants - client-only, no fetch in useEffect, Compiler memo policy.