Tessera MCP Server

Name: Tessera MCP Server
Author: tesseraai

@tesseraaiMCP server · External

MCP server for Tessera's LLM cost-optimization layer: anchored spend, drift, recommendations.

LLM access & routingv0.1.2Apache-2.0TypeScript

Freeno charge per call

How to install

Runs on your machine from its package; the steps are below.

Tessera launch demo — 41-second walkthrough — From the README

What it does

Reads
Writes
High impact

At most: only reads or looks up information.

What it costs

Free

Odel charges nothing per call. The publisher may charge for its own service.

Runs locally over stdio

This server isn't hosted — your MCP client launches it from a package registry. Use one of the commands below, or drop the config into your client (e.g. Claude Desktop).

npm@tessera-llm/mcp-serverv0.1.2

Run

npx -y @tessera-llm/mcp-server

MCP client config

{
  "mcpServers": {
    "tessera-mcp-server": {
      "command": "npx",
      "args": [
        "-y",
        "@tessera-llm/mcp-server"
      ]
    }
  }
}

README3 min readView on GitHub

The MCP server that returns money, not data.

Status: v0.1.3 — published 2026-05-27 on npm with sigstore SLSA provenance v1, listed on registry.modelcontextprotocol.io.

Tessera is an LLM proxy that optimizes API spend through multi-provider routing, prompt compression, audit-immutable logging, output-length prediction, and batch arbitrage. This package exposes Tessera as an MCP server for tool-using agents — Claude Desktop, Claude Code, Cursor, Cline, Continue, Goose, Zed.

Where other LLM-infrastructure MCP servers return logs, traces, or prompt metadata, this one returns savings decisions: what's drifting, what to switch, what to approve, what to audit.

See it in action

▶ 41-second walkthrough: live counter ticks · baseline $74,800 → actual $30,000 ($44,800 saved, 60% reduction) · audit-immutable savings ledger. Click to play.

Install

bash

npx @tessera-llm/mcp-server

Or add to your client config:

Claude Desktop (~/Library/Application Support/Claude/claude_desktop_config.json on macOS, %APPDATA%\Claude\claude_desktop_config.json on Windows):

json

{
  "mcpServers": {
    "tessera": {
      "command": "npx",
      "args": ["-y", "@tessera-llm/mcp-server"],
      "env": {
        "TESSERA_API_KEY": "tk_..."
      }
    }
  }
}

Claude Code (.mcp.json in project root):

json

{
  "mcpServers": {
    "tessera": {
      "command": "npx",
      "args": ["-y", "@tessera-llm/mcp-server"],
      "env": {
        "TESSERA_API_KEY": "tk_..."
      }
    }
  }
}

Cursor (~/.cursor/mcp.json):

json

{
  "mcpServers": {
    "tessera": {
      "command": "npx",
      "args": ["-y", "@tessera-llm/mcp-server"],
      "env": { "TESSERA_API_KEY": "tk_..." }
    }
  }
}

Get a TESSERA_API_KEY at tesseraai.io/dev — Free Sandbox is 60M tokens/month with no card.

Tools

v0.1 exposes 6 tools (5 read + 1 mutate). Hard cap — no tool sprawl.

Tool	Read/Write	Purpose
`tessera_list_workloads`	read	List your mapped workloads with anchor cost + current m-stack.
`tessera_get_savings_report`	read	Anchored spend + measured savings for a window.
`tessera_get_recommendation_queue`	read	Pending Optimize-tab recommendations with expected lift + confidence.
`tessera_get_ledger_entries`	read	Audit-immutable Monthly Reading rows (provider call, mechanic stack applied, savings).
`tessera_get_quality_snapshot`	read	SLA floor + p50/p95 quality scores + drift events.
`tessera_approve_recommendation`	mutate	Move a queued mechanic from "suggested" to "active" with audit-trail entry.

Provider config writes, API-key management, composition cap changes, and Stripe operations are deliberately NOT in this surface — they live in the dashboard, where blast-radius requires explicit modal confirmation.

Transport

stdio (default) — local clients (Claude Desktop, Cursor, Cline, Continue, Claude Code)
Streamable HTTP (optional) — set TESSERA_MCP_TRANSPORT=http to bind on localhost:8788 for remote / Goose / Zed-via-mcp-remote

SSE (deprecated in MCP spec 2025-11-25) is not supported.

Auth

TESSERA_API_KEY env var or Authorization: Bearer <key> header (HTTP transport). Same API key as the SDK — tk_* format. Future v0.2: OAuth 2.1 (aligned with MCP spec RC 2026-07-28).

Security posture

Tools receiving user-controlled content (ledger notes, recommendation rationale strings, workload names) are labelled __untrusted__ to prevent prompt-injection cascade per the Supabase/Cursor 2025 pattern.
mcp-scan (Invariant Labs) runs in CI to catch tool-poisoning attacks in tool descriptions.
No execute_code escape hatch. Typed verbs only.
No session-based auth. Every request authenticates independently per MCP spec 2026 requirement.