_{Banner: Steam header for Eco by Strange Loop Games. Used here for attribution, not my artwork.}

eco-app

The companion service for the Sirens Eco server. It turns live world, trade, crafting, civics, and player state into practical answers, for an agent over MCP or a person in a browser.

One fused service

eco_mcp_app is the core, a data-only MCP server reachable over stdio for Claude Desktop and Streamable-HTTP at /mcp/, whose tools return markdown and structured JSON. Tool names are task-shaped and do not repeat the product name, so get_server_status and get_region rather than get_eco_status.

Mounted inside it: the jobs API at /jobs/api, shaping rows out of the in-game skills mod, and eco_replay, a reader over the replay mod's append-only JSONL event log. frontend/ is the Vite, React, and TypeScript SPA the same service serves at /, with /jobs and /replay pages over those two.

The in-game half

mods/ holds the C# Eco server plugins that feed it: jobs for the skills API, replay for the player-action event store, stores for live store and currency export, and telemetry for logs, metrics, and exception capture.

Gameplay mods live in the sibling eco-mods repo, not here. Main CI builds every real mod project and publishes install-ready ZIPs to Forgejo Packages, per docs/mod-packages.md.

Host files are read, never exposed

The privileged /admin MCP is gone (COI-763). Host-side file questions belong to the node-stats MCP, and the two things this app still reads from the host are a mods tree (get_mods) and one world-generator file (get_world), each behind an env var and each reporting an explicit unavailable state when unmounted. See docs/mcp/FEATURES.md.

Run it

just http           # the fused server against a live eco target
just http-offline   # the same, against the local snapshot fixture
just frontend-dev   # Vite with HMR on :5173, proxying the API

just alone lists every recipe. Each push to canonical main publishes the fused image as forgejo.coilysiren.me/coilyco-gaming/eco-app:<full-source-sha>, and deploy consumes that exact reference through a separate read-only credential.

See also

• AGENTS.md - agent-facing operating rules.
• docs/FEATURES.md - inventory of what ships today.
• justfile - dev verbs.