AWS Amazon Lex Model Building Service
Browse all Amazonaws APIs★ Only Publicly Available OpenAPI DocumentAI/MLLanguage Modelshmac42 EndpointsREST
For Agents
Design and version conversational bots, intents, slot types, and channel integrations for Amazon Lex v1.
Use for: I need to design a chatbot intent for booking appointments, Get the latest version of a Lex bot, List all intents in a bot, Set up a Slack channel association for a bot
Not supported: Does not handle end-user conversation runtime, voice synthesis, or speech-to-text — use for Lex v1 bot authoring, versioning, and channel configuration only.
Jentic publishes the only available OpenAPI specification for Amazon Lex Model Building Service, keeping it validated and agent-ready. The Lex Model Building Service is the v1 control plane for designing conversational bots: defining intents, slot types, slots, and bot aliases that route conversation traffic to specific bot versions. Its 42 endpoints cover intent and slot type lifecycle, bot version management, channel associations for Facebook and Slack, import and export jobs, migration to Lex v2, and tagging. The runtime API for end-user conversations is separate.
Install Jentic One Beta
Connect the Amazon Lex Model Building Service to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Amazon Lex Model Building Service, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Amazon Lex Model Building Service API.
Design intents with utterances and slots via /intents/{name}/versions
Define and version custom slot types via /slottypes/{name}/versions
Create and update bots with /bots/{name}/versions
Associate bots with Facebook, Slack, and Twilio SMS channels
Run import and export jobs to move bot definitions across accounts
Initiate migrations of v1 bots to Amazon Lex v2
Manage bot aliases that route runtime traffic
Use Cases
Patterns agents use Amazon Lex Model Building Service API for, with concrete tasks.
★ Customer Support Chatbot Design
Build a customer support bot that recognises intents such as Refund, OrderStatus, and FAQ, with slots for order numbers and dates. The Lex Model Building Service stores intent utterances, slot types, and fulfilment configurations, then publishes immutable bot versions that can be promoted via aliases. Teams iterate on language without redeploying downstream Lambda fulfilment code.
Create an intent named 'OrderStatus' on bot 'support-bot' with utterances 'where is my order' and 'check order status' and slot orderNumber of type AMAZON.AlphaNumeric
Multi-Channel Bot Deployment
Publish a single bot to multiple channels — Facebook Messenger, Slack, and Twilio SMS — through bot channel associations. The /bots/{botName}/aliases/{aliasName}/channels endpoints record the channel credentials and routing, after which Lex handles message translation and lifecycle on each channel. This avoids writing per-channel adapters by hand.
Create a Slack channel association for bot 'support-bot' alias 'prod' with workspace and bot tokens stored in Secrets Manager
Bot Definition Backups and Migrations
Export bot definitions for version control or migration to a new account. The /exports endpoints serialise bot, intent, and slot type definitions to JSON or ZIP, while /imports reverses the process. The /migrations endpoints initiate a migration of a v1 bot to the v2 console, returning a migration ID that can be polled until completion.
Initiate a migration of bot 'support-bot' alias 'prod' from Lex v1 to Lex v2 using migration strategy CREATE_NEW
AI Agent Conversational Design Operations
AI agents call Lex Model Building through Jentic to author new intents when product features ship, retire stale slots, and migrate v1 bots to v2 in bulk. Through Jentic, the agent searches by intent, loads the operation schema, and executes with credentials kept in the vault. SigV4 signing happens inside Jentic so the agent runtime stays slim.
Search Jentic for 'create lex intent', load the PutIntent schema, and create intent 'CancelSubscription' with three sample utterances
Key Endpoints
42 endpoints — jentic publishes the only available openapi specification for amazon lex model building service, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
PUT
/bots/{name}/versions/$LATEST
Create or update a bot
POST
/bots/{name}/versions
Publish a new bot version
PUT
/intents/{name}/versions/$LATEST
Create or update an intent
PUT
/slottypes/{name}/versions/$LATEST
Create or update a slot type
POST
/bots/{botName}/aliases/{aliasName}/channels/{name}
Associate a channel with a bot alias
POST
/migrations
Start a v1 to v2 migration
PUT
/bots/{name}/versions/$LATEST
Create or update a bot
POST
/bots/{name}/versions
Publish a new bot version
PUT
/intents/{name}/versions/$LATEST
Create or update an intent
PUT
/slottypes/{name}/versions/$LATEST
Create or update a slot type
POST
/bots/{botName}/aliases/{aliasName}/channels/{name}
Associate a channel with a bot alias
POST
/migrations
Start a v1 to v2 migration
Why Jentic?
Three things that make agents converge on Jentic-routed access.
Credential isolation
AWS access keys for Lex are stored encrypted in the Jentic vault. Jentic performs SigV4 signing at execution time, so raw AWS secrets never enter the agent's context.
Intent-based discovery
Agents search Jentic by intent such as 'create lex intent' or 'publish lex bot version' and Jentic returns the matching Lex Model Building operation with its input schema, so the agent calls the right endpoint without parsing AWS docs.
Time to first call
Direct integration: 1-3 days to set up SigV4, IAM, and import/export tooling. Through Jentic: under 1 hour — search, load the schema, execute.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Amazon Lex Model Building Service API through Jentic.
Why is there no official OpenAPI spec for Amazon Lex Model Building Service?
AWS does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Amazon Lex Model Building Service via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.
What authentication does the Lex Model Building API use?
The API uses AWS Signature Version 4 (SigV4) HMAC request signing scoped to the lex IAM service. Through Jentic, AWS credentials sit in the encrypted vault and signing happens at execution time so the agent never sees the raw secret.
Can I author chatbot intents with the Lex Model Building API?
Yes. PUT /intents/{name}/versions/$LATEST creates or updates an intent definition with sample utterances, slots, and fulfilment activity. Custom slot types live under /slottypes and built-in types like AMAZON.AlphaNumeric are referenced by name.
How do I publish a new bot version through Jentic?
Search Jentic for 'publish lex bot version', load the schema for POST /bots/{name}/versions, submit the bot name with the desired checksum, and Jentic will sign and execute the call. Promote that version with an alias update via PUT /bots/{botName}/aliases/{name}.
What are the rate limits for the Lex Model Building API?
Per-region quotas apply, including default caps on bots, intents, slot types per account, and TPS limits on control plane operations. Check the Lex service quotas in the AWS console for the current values in your account.
Does this API run end-user conversations?
No. This API only manages the bot model. Use the Amazon Lex Runtime API to send user utterances to a published bot and receive responses. The Model Building API and the Runtime API are deliberately separate.
Can I migrate a Lex v1 bot to Lex v2?
Yes. POST /migrations starts a migration with a chosen strategy such as CREATE_NEW or UPDATE_EXISTING and returns a migration ID. Poll GET /migrations/{migrationId} until status is COMPLETED or FAILED, then review any returned alerts before promoting the v2 bot.
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