fx now supports custom model connections and themes. Resume, file lookup and request handling are up to 100× faster, long turns use 17× less memory, and libfx adds steering, images, web search and model controls.

Breaking Changes

• Automatic recovery: /continue has been removed. fx now retries and continues on its own.

New Features

• Default model: fx now uses Grok 4.7 as its default model. Fast mode remains opt-in.
• Custom connections: fx now supports named OpenAI Chat Completions connections for local servers and other gateways. Configure them in ~/.fx/settings.json, then select one with fx provider <name> or FX_PROVIDER.
• Provider routing: Gateway users can set provider_order and provider_strict, or pass --provider-order and --provider-strict, to prefer or restrict which providers serve a model.
• Interactive flags: Interactive sessions accept --provider, --model, --effort, and --fast; fx ask accepts --model, --effort, and --fast for one run without changing saved preferences. Grok models now support Fast mode.
• Slack bot: fx can now install and manage your Slack workspace bot from the CLI.
• Custom themes: fx now loads custom TUI themes from ~/.fx/themes/<name>.json, including VS Code themes. Set theme in ~/.fx/settings.json or use FX_THEME.
• Image reading: read_file now attaches PNG, JPEG, GIF, and WebP files to supported vision models.
• libfx steering: libfx turns support turn.steer() for mid-turn guidance. Applied steering arrives as a user_message event and remains in checkpoints.
• libfx model controls: createFxAgent() now accepts image blocks plus effort and fast options. libfx now supports web_search.
• libfx activity: libfx hosts receive transport.activity while responses stream, and tool_start now includes tool input or a bounded preview.
• libfx tool boundaries: libfx now keeps host tools separate from fx's built-in tools, even when they share a name.

Improvements

• Recovery: Transient model failures now retry until the connection recovers. Silent streams use liveness checks, and retries slow to once a minute after 15 minutes.
• Session resume: /resume opens up to 60× faster with better session caching.
• File suggestions: @ file suggestions are 6–40× faster with a saved index and background scanning.
• Gateway setup: Gateway connection setup is up to 48× faster by warming and reusing connections across turns.
• Usage tracking: Usage tracking is over 100× faster on large local histories.
• Memory use: Long tool-heavy turns use over 17× less memory in the release benchmark.
• Compaction: Compaction now preserves conversation history more accurately for better continuation afterward.
• Syntax highlighting: Shell commands and code blocks now have better syntax highlighting across more languages.
• MCP errors: MCP now shows clearer startup and authentication errors, including what to do next.
• MCP forms: Small MCP forms with one choice and up to three options submit directly from the terminal prompt.
• Diagnostics: Logs in /trace and ctrl+o are cleaner and more useful for diagnosing session issues.
• Subagents: Subagent rows show the child's model, effort, token use, and task status. Exact and unambiguous partial model names now work in subagent overrides.
• Faster exits: Double Ctrl+C exits up to 40× faster when MCP servers are stuck, and no longer waits on upgrade downloads.
• Command rendering: Command rows now resize with the terminal, giving long shell commands cleaner rendering.

Bug Fixes

• Multiple images: Reading multiple images in one turn no longer crashes fx, and images returned by tools now reach vision models through Gateway.
• Image accounting: Tool images no longer count as text during request estimation. Automatic compaction now uses the real image cost.
• Session titles: Resuming an untitled session now generates a title from its first committed prompt instead of preserving Untitled session.
• Session saving: A completed turn that fails to save no longer exits fx. The response stays in memory and the save error remains visible.
• Workspace search: grep_files and glob_files no longer end an otherwise completed turn when searching from the workspace root.
• Full-screen views: Typing while ctrl+o or another full-screen view is open no longer disturbs the main conversation. Queued prompt previews also stay clear of active transcript rows.
• Tool recovery: Tool failures now name the unresolved path and tell the model when to reread a file or choose another approach instead of retrying blindly.
• Cancelled recovery: Cancelling response recovery no longer revives the stopped turn on resume. After restarting, the model is also told that old background shell sessions no longer exist.
• MCP capabilities: MCP resources and prompts no longer fail the whole tool call when a server never advertised that capability.
• MCP authentication: Rejected or expired MCP credentials now show needs_auth and the right re-authentication command instead of appearing authenticated.
• Terminal resume: Resumed terminal rows show the recorded launch command, including after moving the workspace, instead of raw session IDs or fixed-width text.
• Transcript retention: Transcript retention no longer overwrites finalized conversation rows or loses pending rows during resize and full-transcript viewing.
• Fast mode fallback: When the model catalog is unavailable, fx reports that the requested Fast mode could not be enabled and continues normally.
• Steering recovery: Steering and response recovery no longer lose buffered assistant output or completed turn summaries.

Security

• Custom connection credentials: Custom connections read credentials only from their named environment variable, and committed project configuration cannot define model endpoints. Saved sessions refuse to resume against a changed endpoint or authentication identity.
• Review model: Set review_model or FX_REVIEW_MODEL to choose the model used for auto-mode safety reviews. Review transport failures and malformed replies retry once; cautions never retry for approval, and an unresolved action stays blocked.
• Safe tool errors: Tool failure details now redact secrets and escape terminal control sequences before rendering.