Image input

docs/claude-protocol.md

@@ -25,7 +25,7 @@ NDJSON both ways: one JSON object per line on stdin and stdout. Non-JSON stdout
 
 ## Messages
 
-- User turn, written to stdin: `{"type":"user","message":{"role":"user","content":"..."},"parent_tool_use_id":null,"session_id":"..."}`.
+- User turn, written to stdin: `{"type":"user","message":{"role":"user","content":"..."},"parent_tool_use_id":null,"session_id":"..."}`. With images, `content` is an array of Anthropic content blocks instead: `{"type":"image","source":{"type":"base64","media_type":"image/png","data":"..."}}` for each image, then `{"type":"text","text":"..."}`.
 - Stdout events: `system` (subtype `init` carries `session_id`, `model`, tools, MCP server status), `assistant` and `user` (Anthropic message content blocks: `text`, `tool_use`, `tool_result`), `result` (ends a turn; `subtype` is `success` or `error_during_execution` after an interrupt, with cost, duration, turn count).
 - `--include-partial-messages` adds `stream_event` lines wrapping the raw API stream (`message_start`, `content_block_start`, `content_block_delta` with `text_delta`, `content_block_stop`, `message_delta`, `message_stop`), each with `parent_tool_use_id` (set inside subagents). The complete `assistant` event for a block still arrives, before that block's `content_block_stop`. Transcripts leave `stream_event` lines out.
 - The `init` event arrives with the first turn, not at launch, so the session ID is unknown until the first message is sent.