This skill handles end-to-end implementation of strict tool use mode (strict: true), ensuring tool input parameters strictly follow your schema. Essential for building reliable agentic workflows with type-safe tool execution.

Use Cases

Multi-Tool Agents: Travel booking, research assistants, etc.
Validated Function Calls: Ensure parameters match expected types
Complex Tool Schemas: Tools with nested properties
Critical Operations: Financial transactions, booking systems
Tool Composition: Sequential and parallel tool execution

Prerequisites

Routed here by structured-outputs-advisor
Model: Claude Sonnet 4.5 or Opus 4.1
Beta header: structured-outputs-2025-11-13

Quick Start

Python:

response = client.beta.messages.create(
    model="claude-sonnet-4-5",
    betas=["structured-outputs-2025-11-13"],
    messages=[{"role": "user", "content": "Search for flights..."}],
    tools=[{
        "name": "search_flights",
        "description": "Search for available flights",
        "strict": True,  # Enable strict validation
        "input_schema": {
            "type": "object",
            "properties": {
                "origin": {"type": "string"},
                "destination": {"type": "string"},
                "travelers": {"type": "integer", "enum": [1, 2, 3, 4, 5, 6]}
            },
            "required": ["origin", "destination", "travelers"],
            "additionalProperties": False
        }
    }]
)

# Tool inputs GUARANTEED to match schema
for block in response.content:
    if block.type == "tool_use":
        execute_tool(block.name, block.input)  # Type-safe!

What You'll Learn

Tool Schema Design - With strict: true and proper validation
Multi-Tool Workflows - Sequential and parallel tool execution
Agent Patterns - Stateful agents, retry logic, validation
Error Handling - Tool failures, refusals, edge cases
Production Deployment - Monitoring, testing, reliability

Examples

travel-booking-agent.py - Multi-tool agent workflow

structured-outputs-advisor - Choose the right mode
json-outputs-implementer - For data extraction

Reference Materials

Version

Current version: 0.1.0

See CHANGELOG.md for version history.

README.md

Strict Tool Implementer

Purpose