--- title: [Learning Notes][Golang] Authorization Challenges in the... description: ID-JAG (Identity Assertion JWT Authorization Grant) is an IETF draft mechanism that addresses authorization challenges when AI Agents act on behalf of users.... canonical: https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: [Learning Notes][Golang] Authorization Challenges in the AI Agent Era: What is ID-JAG and Why I Re-implemented It in Go | daily.dev og:description: ID-JAG (Identity Assertion JWT Authorization Grant) is an IETF draft mechanism that addresses authorization challenges when AI Agents act on behalf of users.... og:url: https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc og:image: https://api.daily.dev/og/posts/7PZZHe2MC.png og:image:alt: [Learning Notes][Golang] Authorization Challenges in the AI Agent Era: What is ID-JAG and Why I Re-implemented It in Go og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # [Learning Notes][Golang] Authorization Challenges in the AI Agent Era: What is ID-JAG and Why I Re-implemented It in Go **[Awesome Go](https://daily.dev/sources/awego)** · 12 min read · 0 upvotes · 0 comments ## Summary ID-JAG (Identity Assertion JWT Authorization Grant) is an IETF draft mechanism that addresses authorization challenges when AI Agents act on behalf of users. Unlike traditional approaches that give agents overly broad permissions or lend user tokens directly, ID-JAG enforces least-privilege at every hop in a multi-layer agent chain. It combines RFC 8693 (OAuth 2.0 Token Exchange) and RFC 7523 (JWT Bearer Grant) to ensure tokens are re-issued and downscoped at each trust boundary. The author re-implemented the reference MCP Server from TypeScript to Go using the official modelcontextprotocol/go-sdk, demonstrating how each tool call triggers a fresh token exchange with only the minimum required scope. The post covers the complete token exchange flow, comparison with PKCE, and hands-on setup instructions with test coverage using httptest to simulate Athenz ZTS. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What is ID-JAG and what problem does it solve for AI agents? ID-JAG (Identity Assertion JWT Authorization Grant) is an authorization mechanism letting AI agents access protected resources on behalf of users while proving a specific user authorized a specific action at a specific moment. It addresses risks from agents holding broad master keys or long-lived user tokens, which lack audit trails and can be exploited via prompt injection. It is still an IETF Internet-Draft, though Athenz and Okta have implemented it and MCP cites the draft. _daily.dev surfaces emerging security drafts like this for teams designing agent authorization before they become standards._ ### What is the difference between OAuth2 PKCE and ID-JAG? PKCE secures a single hop between a user and a public client app by using a code_verifier/code_challenge pair to prevent intercepted authorization codes from being exchanged. ID-JAG instead protects multi-hop delegation chains (IdP to gateway to MCP server to resource server), ensuring each non-human service in the chain proves it is acting under proper authority with minimum necessary permissions at every hop. _developers comparing authorization models for agent chains can track these tradeoffs with daily.dev._ ### How does token downscoping at every hop enforce least privilege in an ID-JAG architecture? Each hop performs its own OAuth 2.0 Token Exchange (RFC 8693) using its own credentials (e.g., mTLS certificate) to swap an incoming token for a new one scoped only to what that specific step needs, rather than forwarding the original token. In one Go MCP server implementation, three tools mapped to distinct Athenz scopes (docs-getter, docs-deleter, docs-poster), so even a broader upstream token gets exchanged down to the minimal scope needed before calling the resource server. _engineers implementing least-privilege agent pipelines can follow architecture writeups like this on daily.dev._ ## Similar posts on daily.dev - [How We Brought Enterprise-Managed Authorization to Rovo MCP with XAA and ID-JAG](https://daily.dev/posts/how-we-brought-enterprise-managed-authorization-to-rovo-mcp-with-xaa-and-id-jag-op8n15tvn) · Atlassian · 0 upvotes · 0 comments - [What is Cross-App Access \(XAA\) and How It Works](https://daily.dev/posts/what-is-cross-app-access-xaa-and-how-it-works-hm360dpyi) · Descope · 0 upvotes · 0 comments - [How to Handle JSON Web Tokens \(JWTs\) in Agentic AI](https://daily.dev/posts/how-to-handle-json-web-tokens-jwts-in-agentic-ai-5ktplpyus) · Nordic APIs · 1 upvotes · 0 comments - [MCP gets its missing enterprise authorization layer](https://daily.dev/posts/mcp-gets-its-missing-enterprise-authorization-layer-9gkkeg9th) · The New Stack · 1 upvotes · 0 comments - [JWTs for AI Agents: Authenticating Non-Human Identities](https://daily.dev/posts/jwts-for-ai-agents-authenticating-non-human-identities-63fw1b4g5) · Security Boulevard · 0 upvotes · 0 comments --- Tags: [#ai-agents](https://daily.dev/tags/ai-agents), [#golang](https://daily.dev/tags/golang), [#authorization](https://daily.dev/tags/authorization), [#jwt](https://daily.dev/tags/jwt) [View this post on daily.dev](https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"[Learning Notes][Golang] Authorization Challenges in the AI Agent Era: What is ID-JAG and Why I Re-implemented It in Go","url":"https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc"},"datePublished":"2026-08-05T07:19:26.073Z","dateModified":"2026-09-14T07:53:02.616Z","description":"ID-JAG (Identity Assertion JWT Authorization Grant) is an IETF draft mechanism that addresses authorization challenges when AI Agents act on behalf of users....","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2e4b4d50e126e350ccff02987edab510?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/2e4b4d50e126e350ccff02987edab510?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Awesome Go","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Awesome Go","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/awego","url":"https://daily.dev/sources/awego"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"ai-agents,golang,authorization,jwt","timeRequired":"PT12M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Awesome Go","item":"https://daily.dev/sources/awego"},{"@type":"ListItem","position":3,"name":"[Learning Notes][Golang] Authorization Challenges in the AI Agent Era: What is ID-JAG and Why I Re-implemented It in Go"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/learning-notes-golang-authorization-challenges-in-the-ai-agent-era-what-is-id-jag-and-why-i-re-i-7pzzhe2mc#faq","mainEntity":[{"@type":"Question","name":"What is ID-JAG and what problem does it solve for AI agents?","acceptedAnswer":{"@type":"Answer","text":"ID-JAG (Identity Assertion JWT Authorization Grant) is an authorization mechanism letting AI agents access protected resources on behalf of users while proving a specific user authorized a specific action at a specific moment. 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