Summary
Tessera's MCP server surfaces LLM cost optimization decisions directly in your AI editor. Install it in Claude Desktop, Cursor, or Cline, pass a TESSERA_API_KEY, and you get six tools: list workloads with their anchor costs, pull savings reports, check queued recommendations with expected lift, browse audit-immutable ledger entries, view quality snapshots with drift events, and approve a mechanic to move it from suggested to active. The read tools let agents diagnose spend, the single write tool lets them act on recommendations with an audit trail. It's designed for teams routing LLM calls through Tessera's proxy and need agents to surface what's drifting or where to switch providers without opening the dashboard.
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one prompt install →tessera-mcp-server
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
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):
{
"mcpServers": {
"tessera": {
"command": "npx",
"args": ["-y", "@tessera-llm/mcp-server"],
"env": {
"TESSERA_API_KEY": "tk_..."
}
}
}
}
Claude Code (.mcp.json in project root):
{
"mcpServers": {
"tessera": {
"command": "npx",
"args": ["-y", "@tessera-llm/mcp-server"],
"env": {
"TESSERA_API_KEY": "tk_..."
}
}
}
}
Cursor (~/.cursor/mcp.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=httpto bind onlocalhost:8788for 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_codeescape hatch. Typed verbs only. - No session-based auth. Every request authenticates independently per MCP spec 2026 requirement.
License
Apache-2.0. Tessera is a product of Fintechagency OÜ (Estonia, Tallinn).
Links
- Tessera landing: tesseraai.io
- Free Sandbox signup: tesseraai.io/dev
- How it works: tesseraai.io/how-it-works
- MCP protocol spec: modelcontextprotocol.io
Featured
Plug Mailtrap into your AI workflow and let it handle the email.
Connect Mailtrap MCP →Agent, run crypto. Access onchain data & trade routes via 1inch.
Install now →Make coding agent sessions - Searchable, Shareable, Vendor-neutral & Scored.
Try For Free →Your agent targets a perfect 10 Code Health score. Deterministic. Every commit.
Try For Free →Integrate web data into your AI product. One API to scrape website & brand data.
Get API Key Now →belt cli automatically finds the best tools and skills for your agent. image, video, music, tts...
one prompt install →Configuration
TESSERA_API_KEY*secretAPI key in tk_* format. Get one free at https://tesseraai.io/dev.
TESSERA_UPSTREAM_API_BASE_URLdefault: https://ledger.tesseraai.ioOverride only for staging or local-dev testing.
Categories
Registryactive
Package@tessera-llm/mcp-server
TransportSTDIO
AuthRequired
UpdatedMay 27, 2026
