effect-facet-unstable-ai-tool

name	effect-facet-unstable-ai-tool
description	Guidance for facet `effect/unstable/ai/Tool` focused on APIs like make, Failure, and FailureMode. Load after `effect-skill-router` when this facet is the primary owner.

Effect Facet unstable/ai/Tool

Owned scope

• Owns only effect/unstable/ai/Tool.
• Parent module: effect/unstable/ai.
• Source anchor: packages/effect/src/unstable/ai/Tool.ts.

What it is for

• The Tool module provides functionality for defining and managing tools that language models can call to augment their capabilities.

API quick reference

• make
• Failure
• FailureMode
• FailureResult
• getJsonSchema
• getStrictMode
• FailureEncoded
• FailureResultEncoded
• getDescription
• getJsonSchemaFromSchema
• providerDefined
• ProviderDefined
• ProviderDefinedTypeId
• isDynamic
• Any
• isUserDefined
• isProviderDefined
• Name
• Full API list: references/api-reference.md

How to use it

• Start with constructor-style APIs to build values/services before composing operations.
• Use schema/codec APIs to validate inputs at boundaries before business logic.
• Treat stateful APIs as synchronization boundaries and keep updates atomic.
• Assume unstable APIs can evolve quickly; isolate usage behind thin local adapters.

Starter example

import { Schema } from "effect";
import { Tool } from "effect/unstable/ai";

// Define a simple calculator tool
const Calculator = Tool.make("Calculator", {
  description: "Performs basic arithmetic operations",
  parameters: Schema.Struct({
    operation: Schema.Literals(["add", "subtract", "multiply", "divide"]),
    a: Schema.Number,
    b: Schema.Number,
  }),
  success: Schema.Number,
});

Common pitfalls

• Unstable module contracts may change; avoid coupling core app logic directly to experimental details.
• Prefer explicit, typed combinators over ad-hoc casting or unchecked assumptions.

Not covered here

• Sibling facets under the same parent are out of scope:
  • effect-facet-unstable-ai-aierror (effect/unstable/ai/AiError)
  • effect-facet-unstable-ai-anthropicstructuredoutput (effect/unstable/ai/AnthropicStructuredOutput)
  • effect-facet-unstable-ai-chat (effect/unstable/ai/Chat)
  • effect-facet-unstable-ai-idgenerator (effect/unstable/ai/IdGenerator)
  • effect-facet-unstable-ai-languagemodel (effect/unstable/ai/LanguageModel)
  • effect-facet-unstable-ai-mcpschema (effect/unstable/ai/McpSchema)
  • effect-facet-unstable-ai-mcpserver (effect/unstable/ai/McpServer)
  • effect-facet-unstable-ai-model (effect/unstable/ai/Model)
  • effect-facet-unstable-ai-openaistructuredoutput (effect/unstable/ai/OpenAiStructuredOutput)
  • effect-facet-unstable-ai-prompt (effect/unstable/ai/Prompt)
  • effect-facet-unstable-ai-response (effect/unstable/ai/Response)
  • effect-facet-unstable-ai-telemetry (effect/unstable/ai/Telemetry)
  • effect-facet-unstable-ai-tokenizer (effect/unstable/ai/Tokenizer)
  • effect-facet-unstable-ai-toolkit (effect/unstable/ai/Toolkit)
• Parent module ownership belongs to effect-module-unstable-ai.

Escalate to

• effect-module-unstable-ai for parent module-wide workflows.
• effect-skill-router for cross-module routing and ownership checks.

Reference anchors

• Facet source: packages/effect/src/unstable/ai/Tool.ts
• Parent tests: packages/effect/test/unstable/ai/Tool.test.ts
• Parent tests: packages/effect/test/unstable/ai/AiError.test.ts
• Parent tests: packages/effect/test/unstable/ai/Chat.test.ts
• Parent tests: packages/effect/test/unstable/ai/LanguageModel.test.ts
• Parent tests: packages/effect/test/unstable/ai/Prompt.test.ts
• Parent tests: packages/effect/test/unstable/ai/AnthropicStructuredOutput.test.ts
• API details: references/api-reference.md
• Usage notes: references/usage-reference.md
• Ownership mapping: references/owner.md