Update 1.5.0-beta

[MathisVerstrepen]

Meridian 1.5.0-beta

Meridian 1.5.0-beta is a large pre-release focused on subscription-backed model access, a rebuilt model selection flow, richer usage visibility, and better runtime support for provider-native coding agents.

Highlights

Subscription Inference Providers

Meridian can now work with multiple subscription-backed provider runtimes alongside metered OpenRouter models.

• Added support for Claude Agent, GitHub Copilot, Z.AI Coding Plan, Gemini CLI, OpenAI Codex, and OpenCode Go.
• Added a new Account Providers settings tab for connecting and disconnecting provider credentials from the UI.
• Subscription models now carry richer metadata, including billing type, connection requirements, and Meridian tool compatibility.
• Available subscription models refresh automatically after provider credentials are added or removed.

Model Selector Redesign

The model dropdown has been redesigned to work well with a much broader catalog.

• Split the dropdown into Pinned Models, per-provider subscription sections, and All Models for metered entries.
• Added section metadata, jump navigation, and virtualization for smoother browsing across large model lists.
• Added better pinned-model handling, including keyboard shortcut support.
• Added warning labels when a model does not support native JSON output.

Usage Data and Cost Visibility

Usage reporting is now much more detailed, especially for multi-request and tool-heavy runs.

• Added normalized usage aggregation with request-level breakdowns.
• Added cost_details support so upstream inference cost components can be shown explicitly.
• Added per-tool usage tracking for subscription providers.
• Redesigned the usage popover to show totals, individual request passes, and parallelization model breakdowns in a clearer way.
• Improved finish-reason and tool-name visibility inside usage details.

Tooling Across Providers

Subscription providers now integrate more deeply with Meridian's tool system.

• Added Meridian tool support across subscription-backed providers for web search, link extraction, code execution, image generation, Visualise, and Ask User.
• Added a provider-aware image generation service path instead of routing everything through the older shared flow.
• Improved tool runtime registration and summary rendering for richer provider-native tool call output.
• Added tool call duration tracking and chat display for faster debugging and better user feedback.

Ask User and Chat Resume Improvements

User-interruptible tool flows are more resilient and easier to continue.

• Added local draft persistence for pending tool questions so answers survive refreshes and accidental navigation.
• Improved resume behavior after submitting tool responses.
• Added better handling for pending tool call IDs across backend services and frontend components.

Canvas and Navigation

• Added a quick-create flow that places new graphs directly inside the currently selected folder or workspace from the home page.
• Improved recent-canvas and sidebar history interactions for folder-heavy workspaces.
• Fixed routing node execution issues.
• Improved parallelization and text-to-text node behavior around cancellation and stream state handling.

Self-Hosting and Upgrade Notes

Self-hosted deployments should treat 1.5.0-beta as an upgrade that adds new runtime requirements.

• Run alembic upgrade head. This release adds a migration for tool call duration tracking.
• Backend environments now need Node.js and npm available for the bundled Gemini CLI and OpenAI Codex bridge runtimes.
• Local installs should also install the runtime package dependencies in api/app/gemini_cli_runtime and api/app/openai_codex_runtime.
• Users who want subscription-backed model access must connect provider credentials from Settings -> Account -> Providers.