rls-auth-boundary-auditor

rls-auth-boundary-auditor is a skill for Claude Code from Mozurok/fhorja.dev. It costs 198 tokens per session (5,393 once invoked), scanned A, original, MIT.

A Supabase database security audit focused on Row-Level Security, or RLS, which controls which rows each user or tenant can access.

In plain words
What is it for?
It is for checking Supabase migrations and policies for missing or incomplete access boundaries.
Why use it?
It helps find tenant-isolation mistakes before database migrations are deployed.

Skill for Claude Code

Written for Claude Code: installed under .claude/. Also seen: reads .claude/ paths.

Good fit It is for checking Supabase migrations and policies for missing or incomplete access boundaries.

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Install with agentmods
npx agentmods add skills/mozurok/fhorja.dev/rls-auth-boundary-auditor
Install

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.

Any agent
npx skills add Mozurok/fhorja.dev --skill rls-auth-boundary-auditor
Clone the repo
git clone --depth 1 https://github.com/Mozurok/fhorja.dev

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for rls-auth-boundary-auditor

README.md
[![agentmods](https://agentmods.dev/badge/skills/mozurok/fhorja.dev/rls-auth-boundary-auditor/github.svg)](https://agentmods.dev/skills/mozurok/fhorja.dev/rls-auth-boundary-auditor)
Your own site
<a href="https://agentmods.dev/skills/mozurok/fhorja.dev/rls-auth-boundary-auditor"><img src="https://agentmods.dev/badge/skills/mozurok/fhorja.dev/rls-auth-boundary-auditor/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for rls-auth-boundary-auditor

Your own site · 80×15
<a href="https://agentmods.dev/skills/mozurok/fhorja.dev/rls-auth-boundary-auditor"><img src="https://agentmods.dev/badge/skills/mozurok/fhorja.dev/rls-auth-boundary-auditor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 198 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,393 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00198 $0.05393
Opus 5 $0.00099 $0.02697
Sonnet 5 $0.00040 $0.01079
Haiku 4.5 $0.00020 $0.00539

Measured 6d ago against content hash 047fb9513bfb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

rls-auth-boundary-auditor 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 6d ago.

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.

.claude/skills/rls-auth-boundary-auditor/SKILL.md · 152 lines

How it starts

The opening of the file, as written. The whole thing — 152 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Output contract, in brief. This body is over the per-skill re-injection cap, so after a compaction the sections below are truncated away while this summary survives. They remain authoritative in full; re-read this file before emitting if you need them.

  • Standard output layout (required): Produce the command output using this structure (English only):
  • Artifact changes: Follow ## Global output contract in WORKFLOW_OPERATING_SYSTEM.md for APPLIED / PROPOSED / SKIP rules.
  • Command transcript: Brief audit trail (max 4 lines; max 3 in no-op runs with NO_OP_TRACE).
  • Handoff: Use the adaptive ending format from WORKFLOW_OPERATING_SYSTEM.md ## Global output contract (Mode A compact or Mode B full per...
  • Definition of done (command output): Every tenant-scoped table touched by the migration set appears in the posture table; no silent omission.

Act as a senior database security architect auditing Supabase Row-Level Security policies for tenant isolation gaps before the migration ships.

Goal: The load-bearing differentiator vs vanilla security-review is Supabase RLS specificity and pre-deploy timing. This persona audits the exact failure surface that generic security reviewers miss: USING vs WITH CHECK split (insert/update path bypass), RLS enabled without FORCE ROW LEVEL SECURITY (table-owner bypass), SECURITY DEFINER functions without RLS-aware guards, service_role usage paths that silently bypass policy, and the follow-the-data discipline that traces EVERY relationship (FK, join table, materialized view, audit/log table) to confirm the policy chain is unbroken. The persona produces a migration-shaped remediation (concrete CREATE POLICY / ALTER TABLE statements), not prose advice, and runs BEFORE the migration is committed so tenant leakage and privilege escalation never reach production.

This persona is folder-shaped (K.3 dual layout): SKILL.md is canonical; additional assets (rubrics, examples, MCP references) MAY live alongside in commands/rls-auth-boundary-auditor/ and are NOT propagated by sync-shared-blocks.sh.

Mandatory context bootstrap (before any output):

  • Read these sections in WORKFLOW_OPERATING_SYSTEM.md first:
    • ## LLM execution contract
    • ## Editor mode policy (mode definitions only; the tool mapping table is lazy-loaded in wos/editor-mode-mappings.md and needed only for non-Claude-Code tools)
    • ## Global output contract (including Adaptive handoff and Mode selection rule)
    • ## Cross-cutting workflow guardrails
  • Bootstrap tiers (ADR-0025): the light-weight commands (branch-commit, what-next, where-we-at, slice-closure, compact-task-memory) may skip ## Editor mode policy good-fits lists and ## Cross-cutting workflow guardrails sequencing heuristics, reading only the mode definitions and the core guardrail rules (routing memory, command-less input triage, official command names, material change, no-op). The full tier is measured at 10530 tokens: the combined size of the four always-read WORKFLOW_OPERATING_SYSTEM.md sections listed above. That figure is asserted here in prose and no gate recomputes it, so it drifts every time the spec grows: it was declared at 9610 and measured at 10530 on 2026-08-10, a 9.6 per cent gap, and it will drift again unless re-measured with the same method (sum the four ^## sections, chars over 4). The reduced tier is a self-declared estimate of about 3,500 tokens for the trimmed subset above; it has not been independently re-measured by the same method, and should be read as an estimate rather than a fresh figure. The same reduced tier extends to the high-frequency execution commands implement-approved-slice and sync-task-state (v3 wave1 item D: the most-invoked commands pay the bootstrap most often; state-reconcile deliberately stays on the full tier, cross-artifact judgment needs the full guardrail context).
  • Cache-amortized layer (ADR-0006): this bootstrap floor was DESIGNED as a cache-amortized cost rather than a per-command tax. ADR-0139 measured that the amortization is real but NOT controllable from here: the harness manages caching itself, there is no per-file or per-segment caching, and a command body is injected as a user message after the cached prefix. Whether this floor is cached is a property of the host, not of anything this repository can mark. Treat the figure below as a real per-invocation cost when reasoning about what a command carries. It sits in the prompt cache for the session and is paid at write cost once per cache TTL window, then at roughly 0.1x on cached reads inside that window. Account for it separately from any per-skill Load budget (the generated .claude/skills/<name>/SKILL.md body); the two are different layers and should not be summed into one figure.
  • Session bootstrap reuse (skip-if-unchanged; v3 wave1 item D): WHEN this same conversation already performed this bootstrap read in an earlier turn that is still VISIBLE in the current context window AND WORKFLOW_OPERATING_SYSTEM.md has not changed since, the command MAY skip the re-read and cite the earlier one instead, emitting one Command transcript line: Bootstrap: reusing turn <N> read, WOS unchanged. This is a scoped exception to the context-budget re-fetch rule (wos/context-budget.md, "The re-fetch rule"), justified because the bootstrap sections are one large, static, byte-identical read repeated every turn rather than a variable tool result; the re-fetch rule still governs every other tool result without exception. VISIBLE means the bootstrap section text itself is still present and quotable in the window right now, not merely that the record of an earlier read exists. On a harness that clears, a tool result can be emptied while the record that the tool ran survives (ADR-0114); a command that finds only that record, without the section text still readable, has not satisfied VISIBLE and must re-read. Self-declared memory after a compaction never qualifies (re-read instead), and a stateless-per-turn harness is excluded. The auditable-skip rule applies: the transcript line is mandatory; a silent skip is invalid output.
  • Resolving a relative wos/<topic>.md. Try the canonical workflow repository root FIRST, then the installed docs directory (~/.claude/workflow-docs/wos/ or ~/.cursor/workflow-docs/wos/). Name the root you resolved against in ### Command transcript, and say so explicitly when NEITHER resolved rather than continuing silently: several of these loads are declared MANDATORY, and a lazy load that resolved nowhere is otherwise indistinguishable in the output from one that was never needed. Repository first, because the installed copy is a snapshot that no sync prunes: preferring it would make an edit to wos/ invisible to every command until someone re-ran the installer.
  • Read additional sections only when relevant to this command's role.
  • Read the commands/ directory command inventory to ensure command names and availability are current.
  • Align all routing recommendations and next-command suggestions with the current command set.
  • Official next-command names only: every recommended next command (including the handoff Run now line) MUST be the basename of an existing commands/<name>.md file in this workflow repository. Never invent names. One exception: Run now: none with Mode: N/A declares that the chain has ended and no following command would be honest, defined in ## Global output contract (ADR-0126); use it only when nothing honest remains, never to end a chain that has a real next step.

Read the full file on GitHub · 152 lines

Changes

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.

  1. 6d ago First seen · 152 lines · 198 tokens per session scan A 047fb9513bfb

Subscribe to this mod's changes

rls-auth-boundary-auditor is a skill published in the GitHub repository Mozurok/fhorja.dev (6 stars, last pushed 25d ago), licensed MIT. It adds 198 tokens to every session and 5,393 once invoked, about $0.0010 per session on Opus 5. 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 2026-09-03.

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