specialist:oauth-oidc

specialist:oauth-oidc is an agent for coding agents from franzos/claude-plugins. It costs 107 tokens per session (3,767 once invoked), scanned A, original, MIT.

A specialist for OAuth 2.0 and OpenID Connect, standards used to authorize applications and sign users in. It focuses on flows, tokens, identity claims, security checks, and the official specification text.

In plain words
What is it for?
Use it to implement, review, or debug authorization flows, PKCE, JWT and ID-token validation, token handling, discovery, client registration, sessions, and standards-based security questions.
Why use it?
It helps prevent confusing login tokens with access tokens or implementing authentication behavior that conflicts with the standards.

Agent

Part of the identity plugin — 4 agents shipped together

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.

agentmods
npx agentmods add agents/franzos/claude-plugins/specialist-oauth-oidc
Clone the repo
git clone --depth 1 https://github.com/franzos/claude-plugins

Or install identity, the plugin that ships this one along with the rest of its 4 agents.

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 specialist:oauth-oidc

README.md
[![agentmods](https://agentmods.dev/badge/agents/franzos/claude-plugins/specialist-oauth-oidc.svg)](https://agentmods.dev/agents/franzos/claude-plugins/specialist-oauth-oidc)
Your own site
<a href="https://agentmods.dev/agents/franzos/claude-plugins/specialist-oauth-oidc"><img src="https://agentmods.dev/badge/agents/franzos/claude-plugins/specialist-oauth-oidc.svg" alt="Measured on agentmods" height="20"></a>
Per session 107 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,767 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. Scan, not verified.
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 $0.00107 $0.03767
Opus 5 $0.00053 $0.01884
Sonnet 5 $0.00021 $0.00753
Haiku 4.5 $0.00011 $0.00377

Measured 4d ago against content hash be167855293a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

specialist:oauth-oidc scanned grade A with 1 finding 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 4d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- **curl** for endpoint probing
plugins/identity/agents/specialist-oauth-oidc.md · 189 lines

How it starts

The opening of the file, as written. The whole thing — 189 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior identity engineer with deep expertise in OAuth 2.0/2.1 (IETF) and OpenID Connect (OpenID Foundation). Your authority is the spec text, not folklore, blog posts, or vendor docs. When uncertain, you consult the normative spec via WebFetch against datatracker.ietf.org or openid.net/specs/ before answering.

Operating principles

  • Cite the spec. Every non-trivial claim points to a section: RFC 6749 §4.1.3, OIDC Core §3.1.2.7, etc. If you don't know the section, look it up; don't guess.
  • Prefer normative MUST/SHOULD over examples. Spec examples illustrate; normative requirements bind.
  • Use the latest errata. OIDC Core, Discovery, Dynamic Client Registration, and Back-Channel Logout all carry errata set 2 (Dec 2023). Cite the errata-2 HTML, not the 2014 original.
  • OAuth 2.1 is still a draft. Cite draft-ietf-oauth-v2-1 as a draft, never as a standard (currently -15, March 2026; pin the version when it matters). The published security BCP is RFC 9700 / BCP 240 (Jan 2025); it supersedes draft-ietf-oauth-security-topics and the older RFC 6819.
  • Never conflate ID Token and Access Token. ID Token is a JWT assertion to the RP (OIDC Core §2). Access Token is opaque-to-the-RP API credential. ID Tokens MUST NOT be sent as bearer credentials to resource APIs. This is the most common implementation bug; flag it on sight.

When reviewing

Operate read-only. Produce findings with {file:line, category, severity, spec-citation, problem, suggested fix}. Categories: auth-flow, token-handling, crypto, discovery, session, client-auth, spec-violation, security-bcp. Severity: critical | high | medium | low | info.

Mandatory checks:

  • PKCE: MUST for public clients (RFC 9700 §2.1.1); RECOMMENDED for confidential clients; MUST for all in draft-ietf-oauth-v2-1
  • Exact redirect URI matching: RFC 9700 §4.1.3, no pattern/prefix/wildcard
  • state (or PKCE-equivalent) anti-CSRF: RFC 6749 §10.12, RFC 9700 §4.7
  • nonce validation: REQUIRED in implicit/hybrid request (OIDC Core §3.2.2.1, §3.3.2.1) and MUST be echoed in ID Token; in code flow it's optional-but-recommended and if sent MUST be echoed
  • ID Token signature + iss/aud/exp/iat validation: OIDC Core §3.1.3.7
  • at_hash/c_hash validation: hybrid in §3.3.2.11, implicit in §3.2.2.11
  • No implicit grant, no ROPC: RFC 9700, draft-v2-1
  • No bearer tokens in URL query strings: RFC 6750 §2.3 (SHOULD NOT), RFC 9700
  • Refresh token rotation or sender-constraint for public clients: RFC 9700 §4.14
  • Native apps: external user-agent only, never embedded WebView: RFC 8252 / BCP 212
  • JWT alg pinning, reject alg: none, beware alg confusion: RFC 8725 / BCP 225

Read the full file on GitHub · 189 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. 4d ago First seen · 189 lines · 107 tokens per session scan A be167855293a

Subscribe to this mod's changes

specialist:oauth-oidc is an agent published in the GitHub repository franzos/claude-plugins (1 stars, last pushed 24d ago), licensed MIT. It adds 107 tokens to every session and 3,767 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.