CDK Parameters

Overview

Bedrock Chat uses a schema-based parameter system powered by Zod for validation. Parameters can be configured in cdk.json (context) or parameter.ts (environment-specific).

Configuration Files

cdk.json

Default parameters for the “default” environment. Located at cdk/cdk.json.

parameter.ts

Environment-specific parameters with type safety. Located at cdk/parameter.ts.

import { BedrockChatParametersInput } from "./lib/utils/parameter-models";

export const bedrockChatParams = new Map<string, BedrockChatParametersInput>();

// Define environments
bedrockChatParams.set("dev", {
  bedrockRegion: "us-east-1",
  enableBotStore: true,
  // ... other parameters
});

bedrockChatParams.set("prod", {
  bedrockRegion: "us-west-2",
  enableBotStore: true,
  enableRagReplicas: true,
  // ... other parameters
});

Deployment:

# Deploy with environment
npx cdk deploy --all --context envName=prod

Base Parameters

Common across all stacks.

envName

string

default:"default"

Environment name (max 10 chars, alphanumeric starting with letter). Used as suffix for stack names and resource prefixes.

envPrefix

string

default:""

Automatically derived from envName. Empty for “default”, otherwise equals envName.

bedrockRegion

string

default:"us-east-1"

AWS region where Amazon Bedrock is available.Common regions: us-east-1, us-west-2, eu-west-1, ap-northeast-1

enableBedrockGlobalInference

boolean

default:true

Enable Bedrock’s global inference routing for automatic model failover.

enableBedrockCrossRegionInference

boolean

default:true

Allow Bedrock to use models from multiple regions for higher availability.

Bedrock Chat Parameters

Main application parameters for BedrockChatStack.

Frontend & Security

enableFrontendWaf

boolean

default:true

Deploy Web ACL for CloudFront distribution.Important: Requires us-east-1 deployment capability. Set to false if you cannot deploy to us-east-1.

enableFrontendIpv6

boolean

default:true

Enable IPv6 for CloudFront distribution.

allowedIpV4AddressRanges

string[]

default:["0.0.0.0/1","128.0.0.0/1"]

Allowed IPv4 CIDR ranges for frontend access (enforced by WAF if enabled).Default: All IPv4 addresses allowedExample: ["203.0.113.0/24", "198.51.100.0/24"]

allowedIpV6AddressRanges

string[]

Allowed IPv6 CIDR ranges for frontend access.Default: All IPv6 addresses allowed

allowedCountries

string[]

default:[]

ISO 3166-1 alpha-2 country codes for geo-restriction.Empty array: No geo-restrictionExample: ["US", "CA", "GB"]

publishedApiAllowedIpV4AddressRanges

string[]

default:["0.0.0.0/1","128.0.0.0/1"]

Allowed IPv4 ranges for published bot APIs.

publishedApiAllowedIpV6AddressRanges

string[]

Allowed IPv6 ranges for published bot APIs.

Authentication

identityProviders

TIdentityProvider[]

default:[]

Array of identity provider configurations for SSO.Format:

[
  {
    "service": "google",
    "secretName": "my-google-idp-secret"
  },
  {
    "service": "oidc",
    "serviceName": "MyOIDC",
    "secretName": "my-oidc-secret"
  }
]

Secrets Manager format:

Google: {"clientId": "...", "clientSecret": "..."}
OIDC: {"clientId": "...", "clientSecret": "...", "issuerUrl": "..."}

userPoolDomainPrefix

string

default:""

Cognito domain prefix for hosted UI. Required if identityProviders is configured.Format: Lowercase alphanumeric and hyphensExample: bedrock-chat-dev

Email domains allowed for self-signup.Empty array: All email domains allowedExample: ["example.com", "acme.org"]

autoJoinUserGroups

string[]

default:["CreatingBotAllowed"]

Cognito groups users automatically join after signup.Available groups: Admin, CreatingBotAllowed, PublishAllowed

Allow users to self-register. Disabled if identity providers are configured.

tokenValidMinutes

number

default:30

Cognito ID token validity in minutes.Range: 5 minutes to 24 hours

Performance & Availability

enableRagReplicas

boolean

default:true

Enable standby replicas for OpenSearch Serverless collections (Knowledge Bases).Impact: Higher availability, ~2x cost

enableLambdaSnapStart

boolean

default:true

Enable Lambda SnapStart for faster cold starts on API and WebSocket handlers.Supported runtimes: Java, Python (3.13+)

Custom Domain

alternateDomainName

string

default:""

Custom domain for the frontend (e.g., chat.example.com).Requirements: Valid ACM certificate will be auto-created in us-east-1

hostedZoneId

string

default:""

Route53 hosted zone ID for DNS record creation. Required if alternateDomainName is set.

Bot Store

enableBotStore

boolean

default:true

Enable bot store for discovering and sharing bots.

enableBotStoreReplicas

boolean

default:false

Enable standby replicas for bot store OpenSearch collection.

botStoreLanguage

BotStoreLanguage

default:"en"

Language for bot store text analysis.Options: en, de, fr, es, ja, ko, zhhans, zhhant, it, nb, th, id, ms

Model Configuration

globalAvailableModels

string[]

default:[]

Restrict available models to specific model IDs.Empty array: All Bedrock models availableExample: ["anthropic.claude-3-5-sonnet-20241022-v2:0", "anthropic.claude-3-5-haiku-20241022-v1:0"]

defaultModel

string

Model ID selected by default when users first visit the app.Example: "anthropic.claude-3-5-sonnet-20241022-v2:0"

titleModel

string

Model used for generating conversation titles.Default: Falls back to defaultModel, then hardcoded default

Branding

logoPath

string

default:""

Path to custom logo file for frontend branding.Format: Relative path from frontend build directory

S3 Configuration

bucketPrefix

string

default:""

Prefix for all S3 bucket names.Format: Lowercase alphanumeric and hyphens onlyExample: "mycompany" creates buckets like mycompany-access-logs, mycompany-frontend-assets

Development

devAccessIamRoleArn

string

default:""

IAM role ARN for developer access to OpenSearch collections.Format: arn:aws:iam::123456789012:role/DeveloperRoleGrants: aoss:* permissions for bot store debugging

API Publish Parameters

Parameters for ApiPublishmentStack (passed via CodeBuild environment variables).

publishedApiThrottleRateLimit

number

Steady-state requests per second.Example: 100

publishedApiThrottleBurstLimit

number

Burst capacity for request handling.Example: 200

publishedApiQuotaLimit

number

Maximum requests per quota period.Example: 10000

publishedApiQuotaPeriod

'DAY' | 'WEEK' | 'MONTH'

Quota period for rate limiting.

publishedApiDeploymentStage

string

default:"api"

API Gateway deployment stage name.

publishedApiId

string

Existing API ID to update (used for redeployment).

publishedApiAllowedOrigins

string

default:"[\"*\"]"

JSON array of allowed CORS origins.Example: '["https://app.example.com", "https://admin.example.com"]'

Custom Bot Parameters

Parameters for BedrockCustomBotStack (passed via CodeBuild environment variables).

ownerUserId

string

required

User ID of the bot creator.

botId

string

required

Unique bot identifier (UUID).

documentBucketName

string

required

S3 bucket name containing bot documents.

knowledge

string

required

JSON-encoded knowledge configuration.Format:

{
  "sourceUrls": ["https://docs.example.com"],
  "filenames": ["document.pdf"],
  "existingS3Urls": ["s3://bucket/prefix/"]
}

knowledgeBase

string

required

JSON-encoded Knowledge Base configuration.Format:

{
  "embeddingsModel": {"modelId": "amazon.titan-embed-text-v2:0"},
  "chunkingStrategy": "fixed-size",
  "maxTokens": 300,
  "overlapPercentage": 20
}

guardrails

string

required

JSON-encoded guardrails configuration.Format:

{
  "is_guardrail_enabled": true,
  "hateThreshold": 3,
  "insultsThreshold": 3,
  "sexualThreshold": 3,
  "violenceThreshold": 3,
  "misconductThreshold": 0,
  "groundingThreshold": 0.75,
  "relevanceThreshold": 0.75
}

Thresholds: 0 (disabled), 1 (low), 2 (medium), 3 (high)

enableRagReplicas

string

default:"false"

Enable replicas for this bot’s Knowledge Base.Values: "true" or "false" (string)

Shared Knowledge Bases Parameters

Parameters for BedrockSharedKnowledgeBasesStack (passed via CodeBuild environment variables).

sharedKnowledgeBases

string

required

JSON-encoded array of shared Knowledge Base configurations.Format:

[
  {
    "knowledgeBaseHash": "abc123",
    "embeddingsModel": {"modelId": "amazon.titan-embed-text-v2:0"},
    "chunkingStrategy": "semantic",
    "instruction": "Custom KB instructions"
  }
]

documentBucketName

string

required

S3 bucket containing shared documents.

enableRagReplicas

string

default:"false"

Enable replicas for shared Knowledge Bases.

Parameter Validation

All parameters are validated using Zod schemas in cdk/lib/utils/parameter-models.ts. Validation rules:

envName: Max 10 chars, alphanumeric, starts with letter
bucketPrefix: Lowercase alphanumeric + hyphens, suitable for S3 naming
IP ranges: Valid CIDR notation
Model IDs: String format (not validated against Bedrock catalog)

Error handling:

# Invalid parameter example
$ npx cdk deploy

Error: Validation error: Invalid input at "envName": String must match pattern /^$|^[a-zA-Z][a-zA-Z0-9]*$/

Environment Variables

Runtime environment variables are automatically set by CDK for Lambda functions and CodeBuild projects. These are not user-configurable parameters. Common Lambda environment variables:

CONVERSATION_TABLE_NAME
BOT_TABLE_NAME
BEDROCK_REGION
DOCUMENT_BUCKET
USER_POOL_ID
TABLE_ACCESS_ROLE_ARN
ENABLE_BEDROCK_GLOBAL_INFERENCE
ENABLE_BEDROCK_CROSS_REGION_INFERENCE

See construct documentation for complete lists per Lambda function.

REST API

CDK API

Overview

Configuration Files

cdk.json

parameter.ts

Base Parameters

Bedrock Chat Parameters

Frontend & Security

Authentication

Performance & Availability

Custom Domain

Bot Store

Model Configuration

Branding

S3 Configuration

Development

API Publish Parameters

Custom Bot Parameters

Shared Knowledge Bases Parameters

Parameter Validation

Environment Variables

Build docs developers (and LLMs) love

REST API

CDK API

​Overview

​Configuration Files

​cdk.json

​parameter.ts

​Base Parameters

​Bedrock Chat Parameters

​Frontend & Security

​Authentication

​Performance & Availability

​Custom Domain

​Bot Store

​Model Configuration

​Branding

​S3 Configuration

​Development

​API Publish Parameters

​Custom Bot Parameters

​Shared Knowledge Bases Parameters

​Parameter Validation

​Environment Variables

Build docs developers (and LLMs) love

Overview

Configuration Files

cdk.json

parameter.ts

Base Parameters

Bedrock Chat Parameters

Frontend & Security

Authentication

Performance & Availability

Custom Domain

Bot Store

Model Configuration

Branding

S3 Configuration

Development

API Publish Parameters

Custom Bot Parameters

Shared Knowledge Bases Parameters

Parameter Validation

Environment Variables