Claude Code Adapter

Capture Claude Code hooks and stream-json output, generate hook settings, and understand model replay limitations.

@isplay/adapter-claude-code captures Claude Code managed runtime evidence through hooks and stream-json ingestion.

Exports

Export	Purpose
`createClaudeCodeAdapter(options?)`	Returns capabilities, hook handler, stream line ingestor, and stream event ingestor.
`claudeCodeCapabilities`	Capability manifest for Claude Code.
`ClaudeCodeHookHandler`	Handles prompt, pre-tool, post-tool, and stop hooks.
`ClaudeStreamIngestor`	Converts stream-json events into model records and events.
`createClaudeCodeSettings(command?)`	Emits Claude Code hook settings.

Setup

import { init } from "@isplay/sdk";
import { createClaudeCodeAdapter } from "@isplay/adapter-claude-code";

init({
  projectId: process.env.ISPLAY_PROJECT_ID!,
  baseUrl: process.env.ISPLAY_API_URL,
});

const claude = createClaudeCodeAdapter({
  runKey: (event) => String(event.session_id ?? "claude-code"),
  replacementMode: "post_tool_context",
});

Hook Handling

const output = await claude.handleHook(input);

Event	Captured behavior
`UserPromptSubmit`	Records event, annotates prompt, optionally returns additional context.
`PreToolUse`	Records proposal, starts tool execution, consults fixture gateway, can deny or defer.
`PostToolUse`	Finishes tool execution and can add injected output as post-tool context.
`Stop`	Annotates final assistant message.

The settings helper also lists PreCompact, SubagentStart, and SubagentStop, but the current handler only special-cases prompt, pre/post tool, and stop.

Stream-JSON Ingestion

await claude.ingestStreamLine(line);
await claude.ingestStreamEvent(event);

Event type	Capture
`system`	Ensures a model call exists and records stream event.
`assistant`	Ensures a model call exists and records stream event.
`result`	Finishes the model call with output and usage.
other	Records stream event.

Settings Generation

import { createClaudeCodeSettings } from "@isplay/adapter-claude-code";

const settings = createClaudeCodeSettings("isplay-claude-hook");

The generated object configures command hooks for user prompt, pre-tool, post-tool, stop, compact, and subagent events.

Capabilities

Claude Code is managed_replay.

Primitive	Status	Mode
Context inventory	`managed_replay`	`observe_only`
Prompt patch	`managed_replay`	`native_replace`
Model capture	`observability_only`	`observe_only`
Model replay	`unsupported`	`observe_only`
Tool capture	`managed_replay`	`observe_only`
Tool fixture replay	`managed_replay`	`post_result_replace`
Checkpointing	`managed_replay`	`observe_only`

Warnings

Claude Code does not expose a stable public model-output injection API, so model replay is unsupported.
Built-in tool output replacement after execution cannot undo side effects.
Use deny/defer before execution for risky tools and isplay-owned MCP/proxy tools for fixture-safe replay.