- Skill ID
- aws/agent-toolkit-for-aws/aws-auth
- Publisher
- aws
- Repository
- agent-toolkit-for-aws
- Installs
- 0
- Files
- 10
- Synced
- Sep 23, 2026
Open any RiverX project, open the Skills panel in the chat, and search for this identifier. The files are fetched from the source repository at install time.
aws/agent-toolkit-for-aws/aws-authInstalls these files- SKILL.md
- references/api-authorization.md
- references/identity-pools.md
- references/lambda-triggers.md
- references/managed-login-oauth.md
- references/passkeys.md
- references/threat-protection.md
- references/tokens-and-sessions.md
- references/troubleshooting.md
- references/user-pools.md
What this skill tells the agent
AWS Auth (Amazon Cognito)
Application-level user authentication and authorization with Amazon Cognito and the Amplify client auth libraries. Verify specific limits, quotas, and exact API shapes against official AWS documentation when precision matters; trust the docs over memory when they conflict.
Recommended: The AWS MCP server provides streamlined access to the AWS APIs used in this skill (Cognito user pool/app client/identity pool setup, API Gateway authorizers). If it is unavailable, the AWS CLI commands shown throughout work directly — the skill has no hard dependency on MCP.
When NOT to use: Amplify Gen2 backend code (defineAuth, amplify/auth.ts, npx ampx); IAM policy/role/trust-policy authoring, STS, or IAM Identity Center console SSO; API Gateway route/integration setup or Lambda function implementation (this skill covers only the Cognito/JWT authorizer configuration and the purpose of Cognito Lambda triggers).
User Pool vs Identity Pool — pick first
These are different services that are frequently confused. Most apps need a user pool; add an identity pool only if the client must call AWS services directly.
| You need... | Use | Why |
|---|---|---|
| Sign-up / sign-in, user directory, issue JWTs | User pool | It authenticates users and is an OIDC IdP |
| The signed-in client to call S3/DynamoDB/etc. directly with AWS credentials | Identity pool | It exchanges a token for temporary AWS credentials via STS |
| Both (sign in, then hit AWS resources from the browser/app) | User pool → identity pool | Identity pool trusts the user pool as its IdP |
If your app only calls your own backend/API, you do not need an identity pool — send the user pool token to your API. See identity-pools.md.
Critical Warnings
`update-user-pool-client` and `set-identity-pool-roles` are FULL REPLACE, not partial updates: Any field you omit is reset to its default — calling update-user-pool-client with only the fields you want to change silently wipes ExplicitAuthFlows, token validity, EnableTokenRevocation, refresh-token rotation, and read/write attributes; set-identity-pool-roles likewise replaces the whole roles + RoleMappings structure. Always read-modify-write: describe-user-pool-client (or get-identity-pool-roles) first, then re-send every existing field plus your change. In an agent context the wipe is invisible — the call succeeds and only breaks later when a user hits the missing flow. See managed-login-oauth.md and identity-pools.md.
Don't use the implicit grant for new apps: The implicit grant (response_type=token) is legacy and returns tokens in the URL fragment. Use the authorization code grant with PKCE (response_type=code + code_challenge) for SPAs and mobile — public clients, no client secret. See managed-login-oauth.md.
Don't store refresh tokens in localStorage for high-value apps: localStorage is readable by any injected script (XSS). The Amplify client library defaults to localStorage; switch to cookieStorage, keep refresh-token lifetime short, and enable refresh token rotation + token revocation on the app client. See tokens-and-sessions.md.
Access-token claim customization needs a paid feature plan: The pre token generation trigger customizes the ID token on the entry-level plan (V1), but customizing the access token (V2/V3) requires a paid feature plan — check the Cognito feature plans documentation for which plan currently includes this, as plan names and inclusions can change. Don't assume access-token claims work on the entry-level plan. See lambda-triggers.md.
App client secret + SPA = broken auth: A public client (browser/mobile) must have no client secret. If a secret is set, token calls fail unless a SECRET_HASH is sent, which a browser cannot protect. Generate a secret only for confidential (server-side) clients.
Don't bulk `admin-confirm-sign-up` UNCONFIRMED users: When users are stuck UNCONFIRMED, prefer resend-confirmation-code so each user re-verifies via confirm-sign-up and proves email ownership (the code likely expired or went to spam). admin-confirm-sign-up flips the status instantly but confirms the account without verifying the email — the attribute stays unverified, which is dangerous when email drives password reset or account linking. Reserve it for trusted/migrated accounts. See troubleshooting.md.
Quick Navigation
| You want to... | Go to |
|---|---|
| Create a user pool, sign-up/sign-in, MFA, password policy, app clients | user-pools.md |
| Add hosted UI / managed login, OAuth flows, social or SAML login, callback URLs, custom domain (ACM in us-east-1) | managed-login-oauth.md |
| Handle ID/access/refresh tokens, rotation, revocation, session termination (global sign-out vs revoke vs disable) | tokens-and-sessions.md |
| Give the client temporary AWS credentials, guest access, role mapping | identity-pools.md |
| Protect an API Gateway API with Cognito tokens (and enforce custom claims in the backend) | api-authorization.md |
Add Cognito login in front of an Application Load Balancer (ALB authenticate-cognito) | api-authorization.md |
| Machine-to-machine (client credentials) auth, resource servers, custom scopes | managed-login-oauth.md |
Create user pool groups and add users to them (cognito:groups, Precedence) | user-pools.md |
| Customize claims, custom auth challenge flows, migrate users, validate sign-up | lambda-triggers.md |
Add passkey / WebAuthn sign-in (USER_AUTH flow, AllowedFirstAuthFactors, WebAuthn enrollment) | passkeys.md |
| Configure threat protection — compromised-credentials block, adaptive auth (risk-based MFA), log delivery to CloudWatch | threat-protection.md |
| Something is broken (redirect, token, MFA, CORS, social login) | troubleshooting.md |
Common Workflows
"Add sign-up and login to my React app" → Create a user pool + a public app client (no secret), enable the hosted UI / managed login with the authorization code grant with PKCE, wire the Amplify client library. See user-pools.md and managed-login-oauth.md.
"Add Google / social login" → Register the social IdP on the user pool, map attributes, add the provider to the app client and hosted UI. See managed-login-oauth.md.
"Only authenticated users should call my API" → HTTP API → JWT authorizer; REST API → Cognito user pools authorizer. See api-authorization.md.
"Let the browser upload to S3 after login" → User pool for sign-in, then an identity pool to vend scoped temporary credentials. See identity-pools.md.
Troubleshooting
| Error/Symptom | Likely Cause | Quick Fix |
|---|---|---|
redirect_mismatch / redirect to wrong URL after login | Callback URL not registered, or scheme/trailing-slash/case differs | Add the exact callback URL (incl. scheme and path) to the app client's Allowed callback URLs |
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