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Creating Custom Tools

Learn how to create, configure, and manage custom tools in Reeva.

What Are Custom Tools?​

Custom Tools are your personalized configurations of Reeva's base tools. They allow you to:

  • Set default parameters - Pre-fill common values to simplify usage
  • Link credentials - Connect your service accounts once and reuse
  • Name descriptively - Use meaningful names that describe their purpose
  • Reuse across servers - Create once, use in multiple servers
  • Maintain consistency - Ensure the same configuration across projects

Base Tools vs Custom Tools​

Base Tools are the 70+ integrations built and maintained by Reeva:

  • Generic, unconfigured
  • Available to all users
  • Cannot be modified
  • Examples: google_search, firecrawl_scrape, notion_create_page

Custom Tools are your instances of base tools:

  • Personalized configuration
  • Owned by your account
  • Can be edited or deleted
  • Examples: "My Blog Scraper", "Company Notion Search", "Dev Jira Tickets"

Example​

Base Tool: firecrawl_scrape

{
  "name": "firecrawl_scrape",
  "parameters": {
    "url": "required",
    "formats": "optional",
    "onlyMainContent": "optional"
  }
}

Custom Tool: "Blog Content Scraper"

{
  "name": "Blog Content Scraper",
  "base_tool": "firecrawl_scrape",
  "param_overrides": {
    "formats": ["markdown"],
    "onlyMainContent": true
  },
  "credential_id": "my_firecrawl_account"
}

Now when AI uses "Blog Content Scraper", it only needs to provide the url - the other parameters are pre-configured.

Creating Custom Tools​

Via Dashboard​

  1. Navigate to Custom Tools

    • Go to Dashboard → Custom Tools
    • Click "Create Custom Tool"

  2. Select Base Tool

    • Browse by category or search by name
    • Click on the base tool you want to configure
    • Review the tool's description and parameters

  3. Configure Your Tool

    • Name: Give it a descriptive name (e.g., "My Company Jira")
    • Description: Optional notes about its purpose
    • Parameter Overrides: Set default values for any parameters
    • Credentials: Link your account if required

  4. Save and Test

    • Click "Create"
    • Test in the Chat Playground before deploying

Via API​

curl -X POST https://api.joinreeva.com/api/custom-tools \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My Web Search",
    "description": "Configured for 10 results",
    "base_tool_id": "tool_google_search",
    "param_overrides": {
      "num_results": 10
    }
  }'

Parameter Overrides​

Parameter overrides allow you to set default values for tool parameters. When the tool is called, these defaults are used unless explicitly overridden.

How Overrides Work​

Priority Order:

  1. Values provided at runtime (highest priority)
  2. Parameter overrides in custom tool
  3. Base tool defaults (lowest priority)

Example: Web Search Configuration​

Base Tool Parameters:

{
  "query": "required",
  "num_results": "optional, default: 10",
  "safe_search": "optional, default: moderate"
}

Custom Tool Overrides:

{
  "param_overrides": {
    "num_results": 20,
    "safe_search": "strict"
  }
}

Runtime Call:

{
  "query": "MCP protocol"
}

Actual Execution:

{
  "query": "MCP protocol",
  "num_results": 20,
  "safe_search": "strict"
}

When to Use Overrides​

✅ Good Use Cases:

  • Setting consistent output formats (formats: ["markdown"])
  • Defining result limits (num_results: 5)
  • Configuring behavior (onlyMainContent: true)
  • Setting default models (model: "sonar-pro")

❌ Avoid:

  • Overriding values that should vary per call (like search queries)
  • Setting very restrictive constraints
  • Duplicating required parameters

Credential Linking​

Many tools require authentication to external services. You link credentials when creating custom tools.

Services Requiring Credentials​

  • Firecrawl: API key
  • Notion: OAuth connection
  • Jira: API token + domain
  • Perplexity: API key
  • N8N: API key + instance URL
  • Supabase: API key + project URL
  • Mem0: API key

Linking Process​

  1. Create Account First

    • Dashboard → Accounts → Add Account
    • Select service and authenticate
    • Save credentials

  2. Link to Custom Tool

    • When creating custom tool
    • Select the credential from dropdown
    • Save

  3. Automatic Injection

    • When the tool executes, credentials are automatically injected
    • You never expose credentials in tool calls
    • Credentials can be rotated without updating custom tools

Example: Notion Custom Tool​

{
  "name": "My Company Notion",
  "base_tool_id": "notion_search_pages",
  "credential_id": "account_abc123",
  "param_overrides": {
    "page_size": 10
  }
}

When this tool runs:

  • Your Notion OAuth token is automatically injected
  • AI can search Notion without knowing your credentials
  • You can update the OAuth token without changing the custom tool

Managing Custom Tools​

Listing Your Tools​

Via Dashboard:

  • Navigate to Custom Tools
  • Filter by category, base tool, or search by name
  • See which servers use each tool

Via API:

curl -X GET https://api.joinreeva.com/api/custom-tools

Updating Tools​

You can update:

  • Name and description
  • Parameter overrides
  • Linked credentials
  • Active/inactive status

Via Dashboard:

  • Click on custom tool → Edit → Make changes → Save

Via API:

curl -X PUT https://api.joinreeva.com/api/custom-tools/{custom_tool_id} \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Updated Name",
    "param_overrides": {
      "num_results": 15
    }
  }'

Deleting Tools​

Warning: Deleting a custom tool removes it from all servers using it.

Via Dashboard:

  • Click on custom tool → Delete → Confirm

Via API:

curl -X DELETE https://api.joinreeva.com/api/custom-tools/{custom_tool_id}

Using Custom Tools in Servers​

Once created, custom tools can be added to any of your servers.

Adding to Server​

During Server Creation:

curl -X POST https://api.joinreeva.com/api/servers \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My Research Server",
    "selected_custom_tools": [
      "custom_tool_1",
      "custom_tool_2",
      "custom_tool_3"
    ]
  }'

Updating Existing Server:

curl -X PUT https://api.joinreeva.com/api/servers/{server_id} \
  -H "Content-Type: application/json" \
  -d '{
    "selected_custom_tools": [
      "custom_tool_1",
      "custom_tool_2",
      "custom_tool_3",
      "custom_tool_4"
    ]
  }'

Reusing Tools​

Custom tools can be used in multiple servers:

Custom Tool: "My Firecrawl Scraper"
├── Server 1: "Research Server"
├── Server 2: "Content Aggregator"
└── Server 3: "Documentation Builder"

Benefits:

  • Consistent configuration across projects
  • Update once, applies everywhere
  • Easier to manage credentials

Best Practices​

Naming Conventions​

✅ Good Names:

  • "Company Jira - Production"
  • "Blog Content Scraper"
  • "Research Perplexity"
  • "Dev Notion Workspace"

❌ Poor Names:

  • "Tool 1"
  • "test"
  • "firecrawl"
  • "my_tool"

Tips:

  • Include the service name
  • Describe the purpose or scope
  • Differentiate between environments (dev/prod)
  • Use clear, descriptive language

Organization Strategies​

By Project:

- "ProjectX Jira"
- "ProjectX Notion"
- "ProjectX Web Search"

By Purpose:

- "Quick Web Search" (5 results)
- "Deep Web Search" (20 results)
- "News Search" (Google News)

By Environment:

- "Production Supabase"
- "Staging Supabase"
- "Dev Supabase"

Parameter Override Guidelines​

  1. Keep it Simple: Only override what's necessary
  2. Document Reasons: Use descriptions to explain why
  3. Test Thoroughly: Verify overrides work as expected
  4. Review Regularly: Remove overrides that aren't used

Security Best Practices​

  1. Credential Hygiene:

    • Use separate credentials for dev/staging/prod
    • Rotate credentials every 90 days
    • Revoke unused credentials immediately

  2. Access Control:

    • Create separate custom tools for different teams
    • Use descriptive names to track usage
    • Monitor which servers use which tools

  3. Audit Trail:

    • Check usage logs regularly
    • Review credit consumption by tool
    • Investigate unexpected usage patterns

Common Patterns​

Research Workflow​

Custom Tool: "Fast Web Search"
├── Base: google_search
├── Overrides: {num_results: 5}
└── No credentials needed

Custom Tool: "Deep Content Scraper"
├── Base: firecrawl_scrape
├── Overrides: {formats: ["markdown"], onlyMainContent: true}
└── Credential: My Firecrawl API Key

Custom Tool: "AI Research Assistant"
├── Base: Perplexity_Ask
├── Overrides: {model: "sonar-pro", temperature: 0.2}
└── Credential: My Perplexity API Key

Productivity Automation​

Custom Tool: "Company Notion"
├── Base: notion_search_pages
├── Overrides: {page_size: 20}
└── Credential: Notion OAuth

Custom Tool: "Dev Team Jira"
├── Base: jira_search_issues
├── Overrides: {project: "DEV", max_results: 50}
└── Credential: Jira API Token

Custom Tool: "Team Gmail"
├── Base: gmail_search
├── Overrides: {max_results: 10}
└── Credential: Gmail OAuth

Data Pipeline​

Custom Tool: "Raw Web Scraper"
├── Base: scrape_webpage
├── No overrides
└── No credentials

Custom Tool: "Clean Text Processor"
├── Base: text processing tools
├── Various text operations
└── No credentials

Custom Tool: "Data Warehouse"
├── Base: supabase_create_records
├── Overrides: {table: "scraped_content"}
└── Credential: Supabase API Key

Troubleshooting​

Tool Not Appearing in Server​

Check:

  • Tool is active (not deactivated)
  • Tool was added to server's selected_custom_tools
  • Server configuration was saved
  • Cache was refreshed (wait 30 seconds)

Credential Errors​

"Invalid credentials" error:

  • Verify credential is linked to custom tool
  • Check credential is still active
  • Re-authenticate if using OAuth
  • Test credential in Accounts section

Override Not Working​

Parameters still using defaults:

  • Check override syntax in custom tool
  • Verify parameter name matches base tool schema
  • Ensure override is saved
  • Test in playground to isolate issue

Permission Denied​

"Access denied" error:

  • Verify you own the custom tool
  • Check credential has necessary permissions
  • Confirm service account has access to resource

Examples​

{
  "name": "Quick News Search",
  "description": "Fast news search with 5 results",
  "base_tool_id": "google_news_search",
  "param_overrides": {
    "num_results": 5,
    "time_range": "24h"
  }
}

Usage in AI:

AI: "Search for latest AI developments"
→ Uses "Quick News Search" with query="latest AI developments"
→ Automatically applies num_results=5 and time_range=24h
{
  "name": "Engineering Docs Search",
  "description": "Search engineering documentation in Notion",
  "base_tool_id": "notion_search_pages",
  "credential_id": "notion_oauth_123",
  "param_overrides": {
    "filter": {
      "property": "Database",
      "database": "engineering_docs"
    },
    "page_size": 10
  }
}

Example 3: Firecrawl Content Extractor​

{
  "name": "Markdown Blog Scraper",
  "description": "Extract blog posts as clean markdown",
  "base_tool_id": "firecrawl_scrape",
  "credential_id": "firecrawl_api_456",
  "param_overrides": {
    "formats": ["markdown"],
    "onlyMainContent": true,
    "excludeTags": ["nav", "footer", "aside"]
  }
}

Next Steps​