api-authorization-and-bola

api-authorization-and-bola is a skill for Claude Code, Codex from JustineDevs/premortem. It costs 36 tokens per session (447 once invoked), scanned A, a copy of api-authorization-and-bola, Apache-2.0.

A testing guide for checking whether an API properly limits access to data and actions. BOLA means a user can access another user's object by changing its identifier, while function-level checks control access to operations such as administration.

In plain words
What is it for?
Use it to test object IDs, nested resources, admin functions, HTTP method variants, and writable fields such as roles or organization IDs.
Why use it?
It provides a focused way to find missing ownership checks, weak routes, alternate methods, and hidden fields that users should not control.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it to test object IDs, nested resources, admin functions, HTTP method variants, and writable fields such as roles or organization IDs.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/justinedevs/premortem/api-authorization-and-bola
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 JustineDevs/premortem --skill api-authorization-and-bola
Clone the repo
git clone --depth 1 https://github.com/JustineDevs/premortem

Made for: Claude Code, Codex.

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 api-authorization-and-bola

README.md
[![agentmods](https://agentmods.dev/badge/skills/justinedevs/premortem/api-authorization-and-bola/github.svg)](https://agentmods.dev/skills/justinedevs/premortem/api-authorization-and-bola)
Your own site
<a href="https://agentmods.dev/skills/justinedevs/premortem/api-authorization-and-bola"><img src="https://agentmods.dev/badge/skills/justinedevs/premortem/api-authorization-and-bola/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 api-authorization-and-bola

Your own site · 80×15
<a href="https://agentmods.dev/skills/justinedevs/premortem/api-authorization-and-bola"><img src="https://agentmods.dev/badge/skills/justinedevs/premortem/api-authorization-and-bola.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 447 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 100% copy Near-identical to another mod 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 $0.00036 $0.00447
Opus 5 $0.00018 $0.00224
Sonnet 5 $0.00007 $0.00089
Haiku 4.5 $0.00004 $0.00045

Measured 9d ago against content hash 449db8e0e1fd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

api-authorization-and-bola 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 9d 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.

Origin

This is a copy

100% identical to api-authorization-and-bola — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/api-authorization-and-bola/SKILL.md · 48 lines

What it actually says

SKILL: API Authorization and BOLA — Object Access, Function Access, and Mass Assignment

AI LOAD INSTRUCTION: Use this skill when an API exposes object IDs, nested resources, or role-sensitive functions and you need a focused authorization test path: BOLA, BFLA, method abuse, and hidden field control.

1. CORE TEST LOOP

  1. Create Account A and Account B.
  2. As Account A, capture create, read, update, and delete flows.
  3. Replay with Account B's token.
  4. Test sibling endpoints, nested endpoints, and alternate HTTP verbs.

2. TEST SURFACES

Surface Example
object read /api/v1/orders/123
nested object /api/v1/users/1/invoices/9
admin or internal function /api/v1/admin/users
update path PUT, PATCH, DELETE variants
hidden JSON fields role, org, verified, tier

3. QUICK PAYLOADS

{"role":"admin"}
{"isAdmin":true}
{"org":"target-company"}
{"verified":true}

4. WHAT TESTERS MISS

  • object IDs in headers, cookies, GraphQL args, and nested objects
  • alternate methods sharing the same route but weaker authz
  • parent check present, child resource check missing
  • admin docs revealing extra writable fields

5. NEXT ROUTING

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. 9d ago First seen · 48 lines · 36 tokens per session scan A 449db8e0e1fd

Subscribe to this mod's changes

api-authorization-and-bola is a skill published in the GitHub repository JustineDevs/premortem (2 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 36 tokens to every session and 447 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to api-authorization-and-bola, differing in 0 lines, and is treated as a copy.