semantica.mcp_server exposes Semantica’s knowledge graph, decision intelligence, semantic extraction, and reasoning capabilities as an MCP (Model Context Protocol) server over stdio:
  • 12 MCP tools exposed: extract entities, query graph, record decisions, run reasoning, export results
  • No Python code required after launch: configure once, use from any MCP-aware client
  • Compatible with Claude Desktop, Windsurf, Cline, Continue, VS Code, Roo Code, Cursor

Server Interface

semantica.mcp_server is a stdio server process, not a Python library. It exposes no importable classes: all interaction happens through MCP tool calls from a connected AI client.
The server communicates over stdio: don’t add logging to stdout. Any print() or logger output directed to stdout will corrupt the JSON-RPC message stream. All logging is written to stderr only. Configure log verbosity with the SEMANTICA_LOG_LEVEL environment variable.

What You Get

  • 12 MCP Tools — Extract entities, extract relations, record decisions, query decisions, find precedents, trace causal chains, add entities, add relationships, run analytics, summarise graph, run reasoning, export graph.
  • 3 Readable Resources — Live graph JSON (semantica://graph/summary), decision list, and schema/version info: readable by any MCP client.
  • Zero Infrastructure — Runs over stdio: no server, no port, no Docker required. One config block to activate in any MCP client.
  • Persistent Graphs — Point SEMANTICA_KG_PATH at a saved graph file to reload it automatically on every server startup.
  • Decision Intelligence — Record decisions, find precedents via hybrid similarity search, and trace causal chains across agent runs.
  • REST Alternative — The Explorer module offers a full HTTP API and browser dashboard if you prefer programmatic access.

Installation

The MCP server is included in the base install: no extras required.

Configuration

1

Find your MCP client's settings file

2

Add the Semantica MCP server config

Configure your MCP client’s command field exactly. The command field must point to the exact executable path (use which semantica-mcp on macOS/Linux to find it). A wrong path fails silently: the server just doesn’t appear in the tools list. Test with the raw echo | semantica-mcp command first to confirm the binary works.
3

Test locally before configuring your client

Environment Variables

The graph starts empty unless you set SEMANTICA_KG_PATH. The MCP server creates a fresh in-memory ContextGraph on first use. Set SEMANTICA_KG_PATH to a previously saved graph file to restore state across server restarts. Without it, all data is lost when the process exits.
Enable debug logging for troubleshooting. Set SEMANTICA_LOG_LEVEL=DEBUG in your MCP client’s env block, or run python -m semantica.mcp_server directly and inspect stderr output.

Tools

The MCP server exposes 12 tools that any connected AI assistant can call:

Knowledge Extraction

Extract named entities (people, places, organisations, concepts) from text using Semantica NER.Input:
Output:
Extract typed relations and (subject, predicate, object) triplets from text.Input:
Output:

Decision Intelligence

Record a decision with full context, reasoning, and metadata into the knowledge graph.Input:
Required fields: category, scenario, reasoning, outcome, confidence. Optional: decision_maker (defaults to "mcp_client"), valid_from, valid_until.Output:
Query recorded decisions by natural language or category filter.Input:
All fields are optional. limit defaults to 10. When query is provided, similarity search is used. When omitted, category filter applies.
Find past decisions similar to a given scenario using hybrid similarity search.Input:
max_results defaults to 5, maximum 50.
Use find_precedents before high-stakes decisions. The tool performs hybrid similarity search across all recorded decisions. Call it at the start of any significant decision path: it surfaces past reasoning that may be directly applicable, reducing redundant work and improving consistency across agent runs.
Trace the causal chain upstream or downstream from a decision.Input:
direction accepts "upstream" or "downstream" (default: "downstream"). max_depth defaults to 5, maximum 20.

Graph Operations

Add a node/entity to the live knowledge graph.Input:
Only id is required. label defaults to the id value. type defaults to "Entity".
Add a directed relationship (edge) between two existing entities.Input:
source and target are required. type defaults to "RELATED_TO".
Return a high-level summary of the current knowledge graph.Output:
Takes no input parameters.
Compute PageRank centrality and community detection over the current graph. Returns top nodes by PageRank, community count, and overall node/edge counts.Takes no input parameters.

Reasoning

Run forward-chaining IF/THEN rules over a set of facts to derive new facts.Input:
Output:

Export

Export the current knowledge graph to a serialisation format.Input:
Supported formats: turtle, ttl, nt, xml, json-ld, json. Default is json-ld.

Resources

The MCP server exposes three readable resources:
  • Context — The ContextGraph that the MCP server operates on.
  • Semantic Extract — NER and relation extraction powering the MCP tools.
  • Reasoning — Forward-chaining engine behind run_reasoning.
  • Agno Integration — Use Semantica inside Agno multi-agent teams.