npm package: @sisu-ai/mw-tool-calling
Description: Legacy compatibility middleware for provider-native tool call loops.
Latest version: 12.0.0

# @sisu-ai/mw-tool-calling

Legacy compatibility middleware for provider-native tool call loops.

> **Recommended for new code:** use core execution middleware from `@sisu-ai/core`:
> - `execute` / `executeWith(opts)` for non-streaming
> - `executeStream` (optionally as `executeStream(opts)`) for streaming

[![Tests](https://github.com/finger-gun/sisu/actions/workflows/tests.yml/badge.svg?branch=main)](https://github.com/finger-gun/sisu/actions/workflows/tests.yml)
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[![License](https://img.shields.io/badge/license-Apache--2.0-blue)](https://github.com/finger-gun/sisu/blob/main/LICENSE)
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## Setup
```bash
npm i @sisu-ai/mw-tool-calling
```

## Behavior
- `toolCalling`: single-round compatibility mode.
  - First turn: calls `ctx.model.generate(messages, { tools, toolChoice:'auto' })`.
  - If assistant returns `tool_calls`, appends the assistant message and executes each tool.
    - Executes each unique `(name, args)` once and responds to every `tool_call_id`.
    - Handles provider quirks by reusing last args for identical tool names with missing args.
  - Second turn: asks for a pure completion (`toolChoice:'none'`).
```mermaid
sequenceDiagram
  autonumber
  participant A as Agent toolCalling
  participant M as Model Adapter
  participant R as Tools Registry
  participant H as Tool Handler

  A->>R: list
  R-->>A: tools
  A->>M: generate with tools auto
  alt tool calls
    M-->>A: assistant with tool calls
    loop each unique name args
      A->>R: resolve and validate
      R-->>A: handler
      A->>H: execute
      H-->>A: append tool message
    end
    A->>M: generate finalize none
    M-->>A: assistant completion
  else no tool calls
    M-->>A: assistant completion
  end

```
- `iterativeToolCalling`: multi-round compatibility mode.
  - Repeats calls with `toolChoice:'auto'` until the model returns a message with no `tool_calls` (max 12 iters).

```mermaid
sequenceDiagram
  autonumber
  participant A as Agent iterativeToolCalling
  participant M as Model Adapter
  participant R as Tools Registry
  participant H as Tool Handler

  A->>R: list
  R-->>A: tools
  loop max twelve iterations until no tool calls
    A->>M: generate with tools auto
    alt tool calls present
      M-->>A: assistant with tool calls
      loop each unique name args
        A->>R: resolve and validate
        R-->>A: handler
        A->>H: execute
        H-->>A: append tool message
      end
    else no tool calls
      M-->>A: assistant no tools
    end
  end
  A->>M: generate finalize none
  M-->>A: assistant completion
```

## Usage
```ts
import { toolCalling, iterativeToolCalling } from '@sisu-ai/mw-tool-calling';

// Single-round
agent.use(toolCalling);

// OR multi-round
agent.use(iterativeToolCalling);
```

## Migration to Core Execution APIs

```ts
import { Agent, execute, getExecutionResult } from '@sisu-ai/core';
import { registerTools } from '@sisu-ai/mw-register-tools';
import { inputToMessage } from '@sisu-ai/mw-conversation-buffer';

const app = new Agent()
  .use(registerTools([myTool]))
  .use(inputToMessage)
  .use(execute);

await app.handler()(ctx); // primary path
console.log(getExecutionResult(ctx)?.text);
```

## Tool Execution Records

Each executed tool call is appended to `ctx.state.toolExecutions`:

```ts
type ToolExecutionRecord = {
  aliasName: string;
  canonicalName: string;
  callId?: string;
  args: unknown;
  result: unknown;
};
```

This is useful for diagnostics and post-run inspection without manually parsing `tool` messages.

# Community & Support

Discover what you can do through examples or documentation. Check it out at https://github.com/finger-gun/sisu. Example projects live under [`examples/`](https://github.com/finger-gun/sisu/tree/main/examples) in the repo.

- [Code of Conduct](https://github.com/finger-gun/sisu/blob/main/CODE_OF_CONDUCT.md)
- [Contributing Guide](https://github.com/finger-gun/sisu/blob/main/CONTRIBUTING.md)
- [License](https://github.com/finger-gun/sisu/blob/main/LICENSE)
- [Report a Bug](https://github.com/finger-gun/sisu/issues/new?template=bug_report.md)
- [Request a Feature](https://github.com/finger-gun/sisu/issues/new?template=feature_request.md)

---

## Documentation

**Core** — [Package docs](packages/core/README.md) · [Error types](packages/core/ERROR_TYPES.md)

**Adapters** — [OpenAI](packages/adapters/openai/README.md) · [Anthropic](packages/adapters/anthropic/README.md) · [Ollama](packages/adapters/ollama/README.md)

<details>
<summary>All middleware packages</summary>

- [@sisu-ai/mw-agent-run-api](packages/middleware/agent-run-api/README.md)
- [@sisu-ai/mw-context-compressor](packages/middleware/context-compressor/README.md)
- [@sisu-ai/mw-control-flow](packages/middleware/control-flow/README.md)
- [@sisu-ai/mw-conversation-buffer](packages/middleware/conversation-buffer/README.md)
- [@sisu-ai/mw-cors](packages/middleware/cors/README.md)
- [@sisu-ai/mw-error-boundary](packages/middleware/error-boundary/README.md)
- [@sisu-ai/mw-guardrails](packages/middleware/guardrails/README.md)
- [@sisu-ai/mw-invariants](packages/middleware/invariants/README.md)
- [@sisu-ai/mw-orchestration](packages/middleware/orchestration/README.md)
- [@sisu-ai/mw-rag](packages/middleware/rag/README.md)
- [@sisu-ai/mw-react-parser](packages/middleware/react-parser/README.md)
- [@sisu-ai/mw-register-tools](packages/middleware/register-tools/README.md)
- [@sisu-ai/mw-tool-calling](packages/middleware/tool-calling/README.md)
- [@sisu-ai/mw-trace-viewer](packages/middleware/trace-viewer/README.md)
- [@sisu-ai/mw-usage-tracker](packages/middleware/usage-tracker/README.md)
</details>

<details>
<summary>All tool packages</summary>

- [@sisu-ai/tool-aws-s3](packages/tools/aws-s3/README.md)
- [@sisu-ai/tool-azure-blob](packages/tools/azure-blob/README.md)
- [@sisu-ai/tool-extract-urls](packages/tools/extract-urls/README.md)
- [@sisu-ai/tool-github-projects](packages/tools/github-projects/README.md)
- [@sisu-ai/tool-rag](packages/tools/rag/README.md)
- [@sisu-ai/tool-summarize-text](packages/tools/summarize-text/README.md)
- [@sisu-ai/tool-terminal](packages/tools/terminal/README.md)
- [@sisu-ai/tool-web-fetch](packages/tools/web-fetch/README.md)
- [@sisu-ai/tool-web-search-duckduckgo](packages/tools/web-search-duckduckgo/README.md)
- [@sisu-ai/tool-web-search-google](packages/tools/web-search-google/README.md)
- [@sisu-ai/tool-web-search-openai](packages/tools/web-search-openai/README.md)
- [@sisu-ai/tool-wikipedia](packages/tools/wikipedia/README.md)
</details>

<details>
<summary>All RAG packages</summary>

- [@sisu-ai/rag-core](packages/rag/core/README.md)
</details>

<details>
<summary>All vector packages</summary>

- [@sisu-ai/vector-core](packages/vector/core/README.md)
- [@sisu-ai/vector-chroma](packages/vector/chroma/README.md)
</details>

<details>
<summary>All examples</summary>

**Anthropic** — [hello](examples/anthropic-hello/README.md) · [control-flow](examples/anthropic-control-flow/README.md) · [stream](examples/anthropic-stream/README.md) · [weather](examples/anthropic-weather/README.md)

**Ollama** — [hello](examples/ollama-hello/README.md) · [stream](examples/ollama-stream/README.md) · [vision](examples/ollama-vision/README.md) · [weather](examples/ollama-weather/README.md) · [web-search](examples/ollama-web-search/README.md)

**OpenAI** — [hello](examples/openai-hello/README.md) · [weather](examples/openai-weather/README.md) · [stream](examples/openai-stream/README.md) · [vision](examples/openai-vision/README.md) · [reasoning](examples/openai-reasoning/README.md) · [react](examples/openai-react/README.md) · [control-flow](examples/openai-control-flow/README.md) · [branch](examples/openai-branch/README.md) · [parallel](examples/openai-parallel/README.md) · [graph](examples/openai-graph/README.md) · [orchestration](examples/openai-orchestration/README.md) · [orchestration-adaptive](examples/openai-orchestration-adaptive/README.md) · [guardrails](examples/openai-guardrails/README.md) · [error-handling](examples/openai-error-handling/README.md) · [rag-chroma](examples/openai-rag-chroma/README.md) · [web-search](examples/openai-web-search/README.md) · [web-fetch](examples/openai-web-fetch/README.md) · [wikipedia](examples/openai-wikipedia/README.md) · [terminal](examples/openai-terminal/README.md) · [github-projects](examples/openai-github-projects/README.md) · [server](examples/openai-server/README.md) · [aws-s3](examples/openai-aws-s3/README.md) · [azure-blob](examples/openai-azure-blob/README.md)
</details>

---

## Contributing

We build Sisu in the open. Contributions welcome.

[Contributing Guide](CONTRIBUTING.md) · [Report a Bug](https://github.com/finger-gun/sisu/issues/new?template=bug_report.md) · [Request a Feature](https://github.com/finger-gun/sisu/issues/new?template=feature_request.md) · [Code of Conduct](CODE_OF_CONDUCT.md)

---

<div align="center">

**[Star on GitHub](https://github.com/finger-gun/sisu)** if Sisu helps you build better agents.

*Quiet, determined, relentlessly useful.*

[Apache 2.0 License](LICENSE)

</div>