Zerno Lite

What the zerno-lite MCP server does

The zerno-lite MCP server connects AI agents to project information stored in ZERNO. It exposes project briefs, task records, compiled agent context, and structured workflows for turning agent findings into reviewable work. The public repository contains metadata, the MCP manifest, and tool definitions; the operational backend is hosted at https://zerno.one/mcp.

The service is intended for coding agents, product agents, and automation workflows that need project orientation before taking action. A project brief can provide the current focus, next action, do-not-do guidance, and a memory index. Agent context combines project memory with recent events for a particular run.

How it works

Connections use Streamable HTTP with JSON-RPC 2.0 requests sent over POST. Authentication uses OAuth 2.1 with PKCE using the S256 method, bearer tokens, and dynamic client registration under RFC 7591. There is no static API key described for setup. Authorization is tied to the user’s permitted ZERNO workspace and project.

The endpoint advertises eight tools, with no MCP resources or prompts. Tool visibility is scope-sensitive: a read-only token receives the four read tools, while authorized write-capable access can expose mutation and creation operations. Calls are audit-logged, bearer tokens are hashed at rest, and tool output does not return secrets.

Setup and configuration

The zerno-lite MCP server is configured as a remote connector named zerno with the URL https://zerno.one/mcp. After adding the connector, complete the OAuth consent flow in a browser. Claude Code and Claude Desktop can add it as a custom connector; Codex CLI supports codex mcp add zerno --url https://zerno.one/mcp; Cursor adds it from its MCP settings using the same URL.

For user-scoped tokens, provide the agent with the relevant project_slug, such as zerno-one, so requests target the intended project. Running the service locally is not an option described by the repository: it is hosted and remote only, with no stdio distribution.

Tools and capabilities

The tool catalog contains these operations:

• zerno_get_project_brief reads project orientation, including focus and next-action information.
• zerno_get_agent_context retrieves compiled project memory and recent events for an agent run.
• zerno_list_tasks returns a filtered backlog listing.
• zerno_get_task retrieves full details for one task.
• zerno_update_task patches task fields or status and recomputes ICE.
• zerno_submit_task_triage creates triage proposals that remain pending human approval.
• zerno_create_agent_intake_task creates a review task from an agent report.
• zerno_capture_session_event appends a session summary to project memory.

Limitations and notes

The zerno-lite MCP server requires a ZERNO account and an authorized project. It cannot be installed as a local stdio server or packaged backend. Its interface consists only of tools; it provides no MCP resources or prompts. Write actions have different effects: task updates mutate existing records, triage submissions create proposals awaiting human approval, intake creates tasks, and session capture creates memory events. The repository’s MIT license applies to its metadata repository.