add-block
The add-block Claude Code slash command generates block configuration files for Sim integrations. Use it when you need to create a new block type with properly configured subBlocks, conditions, tool wiring, and authentication modes for integrating external services into the Sim platform.
mkdir -p ~/.claude/commands && curl -fsSL https://raw.githubusercontent.com/simstudioai/sim/HEAD/.claude/commands/add-block.md -o ~/.claude/commands/add-block.mdadd-block.md
# Add Block Skill
You are an expert at creating block configurations for Sim. You understand the serializer, subBlock types, conditions, dependsOn, modes, and all UI patterns.
## Your Task
When the user asks you to create a block:
1. Create the block file in `apps/sim/blocks/blocks/{service}.ts`
2. Configure all subBlocks with proper types, conditions, and dependencies
3. Wire up tools correctly
## Block Configuration Structure
```typescript
import { {ServiceName}Icon } from '@/components/icons'
import type { BlockConfig } from '@/blocks/types'
import { AuthMode, IntegrationType } from '@/blocks/types'
import { getScopesForService } from '@/lib/oauth/utils'
export const {ServiceName}Block: BlockConfig = {
type: '{service}', // snake_case identifier
name: '{Service Name}', // Human readable
description: 'Brief description', // One sentence
longDescription: 'Detailed description for docs',
docsLink: 'https://docs.sim.ai/tools/{service}',
category: 'tools', // 'tools' | 'blocks' | 'triggers'
integrationType: IntegrationType.X, // Primary category (see IntegrationType enum)
tags: ['oauth', 'api'], // Cross-cutting tags (see IntegrationTag type)
bgColor: '#HEXCOLOR', // Brand color
icon: {ServiceName}Icon,
// Auth mode
authMode: AuthMode.OAuth, // or AuthMode.ApiKey
subBlocks: [
// Define all UI fields here
],
tools: {
access: ['tool_id_1', 'tool_id_2'], // Array of tool IDs this block can use
config: {
tool: (params) => `{service}_${params.operation}`, // Tool selector function
params: (params) => ({
// Transform subBlock values to tool params
}),
},
},
inputs: {
// Optional: define expected inputs from other blocks
},
outputs: {
// Define outputs available to downstream blocks
},
}
```
## SubBlock Types Reference
**Critical:** Every subblock `id` must be unique within the block. Duplicate IDs cause conflicts even with different conditions.
### Text Inputs
```typescript
// Single-line input
{ id: 'field', title: 'Label', type: 'short-input', placeholder: '...' }
// Multi-line input
{ id: 'field', title: 'Label', type: 'long-input', placeholder: '...', rows: 6 }
// Password input
{ id: 'apiKey', title: 'API Key', type: 'short-input', password: true }
```
### Selection Inputs
```typescript
// Dropdown (static options)
{
id: 'operation',
title: 'Operation',
type: 'dropdown',
options: [
{ label: 'Create', id: 'create' },
{ label: 'Update', id: 'update' },
],
value: () => 'create', // Default value function
}
// Combobox (searchable dropdown)
{
id: 'field',
title: 'Label',
type: 'combobox',
options: [...],
searchable: true,
}
```
### Code/JSON Inputs
```typescript
{
id: 'code',
title: 'Code',
type: 'code',
language: 'javascript', // 'javascript' | 'json' | 'python'
placeholder: '// Enter code...',
}
```
### OAuth/Credentials
```typescript
{
id: 'credential',
title: 'Account',
type: 'oauth-input',
serviceId: '{service}', // Must match OAuth provider service key
requiredScopes: getScopesForService('{service}'), // Import from @/lib/oauth/utils
placeholder: 'Select account',
required: true,
}
```
**Scopes:** Always use `getScopesForService(serviceId)` from `@/lib/oauth/utils` for `requiredScopes`. Never hardcode scope arrays — the single source of truth is `OAUTH_PROVIDERS` in `lib/oauth/oauth.ts`.
**Scope descriptions:** When adding a new OAuth provider, also add human-readable descriptions for all scopes in `SCOPE_DESCRIPTIONS` within `lib/oauth/utils.ts`.
### Selectors (with dynamic options)
```typescript
// Channel selector (Slack, Discord, etc.)
{
id: 'channel',
title: 'Channel',
type: 'channel-selector',
serviceId: '{service}',
placeholder: 'Select channel',
dependsOn: ['credential'],
}
// Project selector (Jira, etc.)
{
id: 'project',
title: 'Project',
type: 'project-selector',
serviceId: '{service}',
dependsOn: ['credential'],
}
// File selector (Google Drive, etc.)
{
id: 'file',
title: 'File',
type: 'file-selector',
serviceId: '{service}',
mimeType: 'application/pdf',
dependsOn: ['credential'],
}
// User selector
{
id: 'user',
title: 'User',
type: 'user-selector',
serviceId: '{service}',
dependsOn: ['credential'],
}
```
### Other Types
```typescript
// Switch/toggle
{ id: 'enabled', type: 'switch' }
// Slider
{ id: 'temperature', title: 'Temperature', type: 'slider', min: 0, max: 2, step: 0.1 }
// Table (key-value pairs)
{ id: 'headers', title: 'Headers', type: 'table', columns: ['Key', 'Value'] }
// File upload
{
id: 'files',
title: 'Attachments',
type: 'file-upload',
multiple: true,
acceptedTypes: 'image/*,application/pdf',
}
```
## File Input Handling
When your block accepts file uploads, use the basic/advanced mode pattern with `normalizeFileInput`.
### Basic/Advanced File Pattern
```typescript
// Basic mode: Visual file upload
{
id: 'uploadFile',
title: 'File',
type: 'file-upload',
canonicalParamId: 'file', // Both map to 'file' param
placeholder: 'Upload file',
mode: 'basic',
multiple: false,
required: true,
condition: { field: 'operation', value: 'upload' },
},
// Advanced mode: Reference from other blocks
{
id: 'fileRef',
title: 'File',
type: 'short-input',
canonicalParamId: 'file', // Both map to 'file' param
placeholder: 'Reference file (e.g., {{file_block.output}})',
mode: 'advanced',
required: true,
condition: { field: 'operation', value: 'upload' },
},
```
**Critical constraints:**
- `canonicalParamId` must NOT match any subblock's `id` in the same block
- Values are stored under subblock `id`, not `canonicalParamId`
### Normalizing File Input in tools.config
Use `normalizeFileInput` to handle all input variants:
```typescript
import { normalizeFileInput } from '@/blocks/utils'
tools: {
access: ['service_Add a knowledge base connector for syncing documents from an external source
Add a code-defined table enrichment (registry entry) backed by a provider cascade, ensuring each provider tool has hosted-key support
Add hosted API key support to a tool so Sim provides the key when users don't bring their own. Use when adding hosted keys, BYOK support, hideWhenHosted, or hosted key pricing to a tool or block.
Add a complete integration to Sim (tools, block, icon, registration)
Add a new LLM model to apps/sim/providers/models.ts with specs verified against the provider's live API docs (no hallucination)
Create tool configurations for a Sim integration by reading API docs
Create webhook or polling triggers for a Sim integration
Run all code quality skills in sequence — effects, memo, callbacks, state, React Query, and emcn design review