Add Tools Skill

You are an expert at creating tool configurations for Sim integrations. Your job is to read API documentation and create properly structured tool files.

Your Task

When the user asks you to create tools for a service:

1. Use Context7 or WebFetch to read the service's API documentation
2. Create the tools directory structure
3. Generate properly typed tool configurations

Hard Rule: No Guessed Response Schemas

If the docs do not clearly show the response JSON for a tool, you MUST tell the user exactly which outputs are unknown and stop short of guessing.

• Do NOT invent response field names
• Do NOT infer nested paths from nearby endpoints
• Do NOT guess array item shapes
• Do NOT write transformResponse against unverified payloads

If the response shape is unknown, do one of these instead:

1. Ask the user for sample responses
2. Ask the user for test credentials so you can verify live responses
3. Implement only the endpoints whose outputs are documented
4. Leave the tool unimplemented and explicitly say why

Directory Structure

Create files in apps/sim/tools/{service}/:

tools/{service}/
├── index.ts      # Barrel export
├── types.ts      # Parameter & response types
└── {action}.ts   # Individual tool files (one per operation)

Tool Configuration Structure

Every tool MUST follow this exact structure:

import type { {ServiceName}{Action}Params } from '@/tools/{service}/types'
import type { ToolConfig } from '@/tools/types'

interface {ServiceName}{Action}Response {
  success: boolean
  output: {
    // Define output structure here
  }
}

export const {serviceName}{Action}Tool: ToolConfig<
  {ServiceName}{Action}Params,
  {ServiceName}{Action}Response
> = {
  id: '{service}_{action}',           // snake_case, matches tool name
  name: '{Service} {Action}',         // Human readable
  description: 'Brief description',   // One sentence
  version: '1.0.0',

  // OAuth config (if service uses OAuth)
  oauth: {
    required: true,
    provider: '{service}',            // Must match OAuth provider ID
  },

  params: {
    // Hidden params (system-injected, only use hidden for oauth accessToken)
    accessToken: {
      type: 'string',
      required: true,
      visibility: 'hidden',
      description: 'OAuth access token',
    },
    // User-only params (credentials, api key, IDs user must provide)
    someId: {
      type: 'string',
      required: true,
      visibility: 'user-only',
      description: 'The ID of the resource',
    },
    // User-or-LLM params (everything else, can be provided by user OR computed by LLM)
    query: {
      type: 'string',
      required: false,                // Use false for optional
      visibility: 'user-or-llm',
      description: 'Search query',
    },
  },

  request: {
    url: (params) => `https://api.service.com/v1/resource/${params.id}`,
    method: 'POST',
    headers: (params) => ({
      Authorization: `Bearer ${params.accessToken}`,
      'Content-Type': 'application/json',
    }),
    body: (params) => ({
      // Request body - only for POST/PUT/PATCH
      // Trim ID fields to prevent copy-paste whitespace errors:
      // userId: params.userId?.trim(),
    }),
  },

  transformResponse: async (response: Response) => {
    const data = await response.json()
    return {
      success: true,
      output: {
        // Map API response to output
        // Use ?? null for nullable fields
        // Use ?? [] for optional arrays
      },
    }
  },

  outputs: {
    // Define each output field
  },
}

Critical Rules for Parameters

Visibility Options

• 'hidden' - System-injected (OAuth tokens, internal params). User never sees.
• 'user-only' - User must provide (credentials, api keys, account-specific IDs)
• 'user-or-llm' - User provides OR LLM can compute (search queries, content, filters, most fall into this category)

Parameter Types

• 'string' - Text values
• 'number' - Numeric values
• 'boolean' - True/false
• 'json' - Complex objects (NOT 'object', use 'json')
• 'file' - Single file
• 'file[]' - Multiple files

Required vs Optional

• Always explicitly set required: true or required: false
• Optional params should have required: false

Resolved Secrets and Provenance Boundaries

• Leave ordinary external API inputs and third-party results unchanged. Add provenance handling only when an exact field is proven to cross a Sim model, durable-storage, or internal-execution boundary.
• Project AI-consumed text/structured fields with the smallest exact request.modelInput selector.
• Treat URLs, domains, resource IDs, and control fields as ordinary request values unless the exact field is proven model-visible. For serialized external model content, project the serialized top-level param through request.modelInput before the existing formatter parses it; do not add a separate hard-rejection mechanism.
• For authenticated internal routes, use privateProvenance for actual inline/raw model bytes or request.secretProvenance for durable writes and execution handoffs. Do not treat a storage key, path, signed URL, or remote URL as provenance for fetched bytes; authorize tracked stored bytes at the owning model-egress boundary. Authenticate first, validate the exact selection and scope, strip the private envelope, then import or propagate provenance at the receiving boundary. Preserve documented headerless legacy behavior.
• Never substitute secret plaintext into source, serialize plaintext provenance, hand-roll private headers, or blanket-sanitize tool results.
• Add focused tests for named projection, identical unproven public text, malformed/incomplete metadata, metadata stripping, scope isolation, and legacy compatibility where applicable.

Critical Rules for Outputs

Output Types

• 'string', 'number', 'boolean' - Primitives
• 'json' - Complex objects (use this, NOT 'object')
• 'array' - Arrays with items property
• 'object' - Objects with properties property

Optional Outputs

Add optional: true for fields that may not exist in the response:

closedAt: {
  type: 'string',
  description: 'When the issue was closed',
  optional: true,
},

Typed JSON Outputs

When using type: 'json' and you know the object shape in advance, always define the inner structure using properties so downstream consumers know what fields are available:

// BAD: Opaque json with no info about what's inside
metadata: {
  type: 'json',
  description: 'Response metadata',
},

// GOOD: Define the known properties
metadata: {
  type: 'json',
  description: 'Response metadata',
  properties: {
    id: { type: 'string', description: 'Unique ID' },
    status: { type: 'string', description: 'Current status' },
    count: { type: 'number', description: 'Total count' },
  },
},

For arrays of objects, define the item structure:

items: {
  type: 'array',
  description: 'List of items',
  items: {
    type: 'object',
    properties: {
      id: { type: 'string', description: 'Item ID' },
      name: { type: 'string', description: 'Item name' },
    },
  },
},

Only use bare type: 'json' without properties when the shape is truly dynamic or unknown.

If the response shape is unknown because the docs do not provide it, you MUST tell the user and stop. Unknown is not the same as dynamic. Never guess outputs.

Critical Rules for transformResponse

Handle Nullable Fields

ALWAYS use ?? null for fields that may be undefined:

transformResponse: async (response: Response) => {
  const data = await response.json()
  return {
    success: true,
    output: {
      id: data.id,
      title: data.title,
      body: data.body ?? null,           // May be undefined
      assignee: data.assignee ?? null,   // May be undefined
      labels: data.labels ?? [],         // Default to empty array
      closedAt: data.closed_at ?? null,  // May be undefined
    },
  }
}

Never Output Raw JSON Dumps

DON'T do this:

output: {
  data: data,  // BAD - raw JSON dump
}

DO this instead - extract meaningful fields:

output: {
  id: data.id,
  name: data.name,
  status: data.status,
  metadata: {
    createdAt: data.created_at,
    updatedAt: data.updated_at,
  },
}

Types File Pattern

Create types.ts with interfaces for all params and responses:

import type { ToolResponse } from '@/tools/types'

// Parameter interfaces
export interface {Service}{Action}Params {
  accessToken: string
  requiredField: string
  optionalField?: string
}

// Response interfaces (extend ToolResponse)
export interface {Service}{Action}Response extends ToolResponse {
  output: {
    field1: string
    field2: number
    optionalField?: string | null
  }
}

Index.ts Barrel Export Pattern

// Export all tools
export { serviceTool1 } from './{action1}'
export { serviceTool2 } from './{action2}'

// Export types
export * from './types'

Registering Tools

After creating tools:

1. Import tools in apps/sim/tools/registry.ts
2. Add to the tools object with snake_case keys (alphabetically):

import { serviceActionTool } from '@/tools/{service}'

export const tools = {
  // ... existing tools ...
  {service}_{action}: serviceActionTool,
}

3. Regenerate the tool metadata artifacts:

bun run tool-metadata:generate

Client code reads a tool's params/outputs from generated metadata rather than importing the registry, so a tool you add, change or remove is invisible to the UI until these are regenerated — and CI fails on stale artifacts. Commit the result. See .agents/skills/tool-registry-boundary/SKILL.md.

Wiring Tools into the Block (Required)

After registering in tools/registry.ts, you MUST also update the block definition at apps/sim/blocks/blocks/{service}.ts. This is not optional — tools are only usable from the UI if they are wired into the block.

1. Add to tools.access

tools: {
  access: [
    // existing tools...
    'service_new_action',   // Add every new tool ID here
  ],
  config: { ... }
}

2. Add operation dropdown options

If the block uses an operation dropdown, add an option for each new tool:

{
  id: 'operation',
  type: 'dropdown',
  options: [
    // existing options...
    { label: 'New Action', id: 'new_action' },   // id maps to what tools.config.tool returns
  ],
}

3. Add subBlocks for new tool params

For each new tool, add subBlocks covering all its required params (and optional ones where useful). Apply condition to show them only for the right operation, and mark required params with required:

// Required param for new_action
{
  id: 'someParam',
  title: 'Some Param',
  type: 'short-input',
  placeholder: 'e.g., value',
  condition: { field: 'operation', value: 'new_action' },
  required: { field: 'operation', value: 'new_action' },
},
// Optional param — put in advanced mode
{
  id: 'optionalParam',
  title: 'Optional Param',
  type: 'short-input',
  condition: { field: 'operation', value: 'new_action' },
  mode: 'advanced',
},

4. Update tools.config.tool

Ensure the tool selector returns the correct tool ID for every new operation. The simplest pattern:

tool: (params) => `service_${params.operation}`,
// If operation dropdown IDs already match tool IDs, this requires no change.

If the dropdown IDs differ from tool IDs, add explicit mappings:

tool: (params) => {
  const map: Record<string, string> = {
    new_action: 'service_new_action',
    // ...
  }
  return map[params.operation] ?? `service_${params.operation}`
},

5. Update tools.config.params

Add any type coercions needed for new params (runs at execution time, after variable resolution):

params: (params) => {
  const result: Record<string, unknown> = {}
  if (params.limit != null && params.limit !== '') result.limit = Number(params.limit)
  if (params.newParamName) result.toolParamName = params.newParamName  // rename if IDs differ
  return result
},

6. Add new outputs

Add any new fields returned by the new tools to the block outputs:

outputs: {
  // existing outputs...
  newField: { type: 'string', description: 'Description of new field' },
}

7. Add new inputs

Add new subBlock param IDs to the block inputs section:

inputs: {
  // existing inputs...
  someParam: { type: 'string', description: 'Param description' },
  optionalParam: { type: 'string', description: 'Optional param description' },
}

Block wiring checklist

• New tool IDs added to tools.access
• Operation dropdown has an option for each new tool
• SubBlocks cover all required params for each new tool
• SubBlocks have correct condition (only show for the right operation)
• Optional/rarely-used params set to mode: 'advanced'
• tools.config.tool returns correct ID for every new operation
• tools.config.params handles any ID remapping or type coercions
• New outputs added to block outputs
• New params added to block inputs

V2 Tool Pattern

If creating V2 tools (API-aligned outputs), use _v2 suffix:

• Tool ID: {service}_{action}_v2
• Variable name: {action}V2Tool
• Version: '2.0.0'
• Outputs: Flat, API-aligned (no content/metadata wrapper)

Naming Convention

All tool IDs MUST use snake_case: {service}_{action} (e.g., x_create_tweet, slack_send_message). Never use camelCase or PascalCase for tool IDs.

Checklist Before Finishing

• All tool IDs use snake_case
• All params have explicit required: true or required: false
• All params have appropriate visibility
• All nullable response fields use ?? null
• All optional outputs have optional: true
• No raw JSON dumps in outputs
• Types file has all interfaces
• Index.ts exports all tools and re-exports types (export * from './types')
• Tools registered in tools/registry.ts
• bun run tool-metadata:generate run and the regenerated artifacts committed
• bun run scripts/generate-docs.ts run and the refreshed docs committed — the integration's docs page is rendered from each tool's description, params, and outputs, and CI's bun run docs:check fails on stale pages
• Block wired: tools.access, dropdown options, subBlocks, tools.config, outputs, inputs
• Model, durable-storage, and internal-execution boundaries use the shared provenance mechanisms only where a concrete Sim {{...}} resolution path requires them
• Ordinary third-party inputs/results remain unchanged and private metadata never leaves Sim

Final Validation (Required)

After creating all tools, you MUST validate every tool before finishing:

1. Read every tool file you created — do not skip any
2. Cross-reference with the API docs to verify:
   • All required params are marked required: true
   • All optional params are marked required: false
   • Param types match the API (string, number, boolean, json)
   • Request URL, method, headers, and body match the API spec
   • transformResponse extracts the correct fields from the API response
   • All output fields match what the API actually returns
   • No fields are missing from outputs that the API provides
   • No extra fields are defined in outputs that the API doesn't return
   • Every output field and JSON path is backed by docs or live-verified sample responses
3. Verify consistency across tools:
   • Shared types in types.ts match all tools that use them
   • Tool IDs in the barrel export match the tool file definitions
   • Error handling is consistent (error checks, meaningful messages)
4. If any response schema is still unknown, explicitly tell the user instead of guessing