KeGAL - Kedos Graph Agent for LLM

KeGAL is a graph-based agent framework for LLMs. It enables the development of workflows structured as graphs, where each node represents an agent, and input and output messages are formatted as structured JSON files.

An agent can be designed using prompt engineering for specific tasks. Additionally, each agent can utilize tools written in Python to connect to external knowledge sources. Moreover, agents can invoke external services via HTTP, allowing seamless integration with various systems.

The core concept of KeGAL is to leverage one or more LLMs to manage workflow execution within the architecture. Agents contain no traditional code; instead, everything is controlled by the LLM through its tooling capabilities.

Installation

Install from PyPI with the provider(s) you need:

pip install "kegal[anthropic]"   # Anthropic
pip install "kegal[openai]"      # OpenAI
pip install "kegal[gemini]"      # Google Gemini
pip install "kegal[ollama]"      # Ollama (local)
pip install "kegal[aws]"         # AWS Bedrock
pip install "kegal[all]"         # all providers

Or clone and install in development mode (all providers):

git clone https://github.com/kedos-srl/kegal.git
cd kegal
pip install -e ".[all]"

Documentation

Full documentation is available at https://kedos-srl.github.io/kegal/

• Graph Reference - Full field reference for the Graph model hierarchy
• LLM Providers - Guide on LLM providers and integration
• Tutorials - 13 topic tutorials from basics to advanced: structured output, RAG, chat history, blackboard, ReAct, and more
• Changelog - Version history and release notes

Quick Start

Basic usage

from kegal import Compiler

compiler = Compiler(uri="path/to/your_graph.yml")
compiler.compile()
outputs = compiler.get_outputs()

Always release the compiler when you are done. It frees:

• MCP servers — stopped and their background threads joined (only if the graph uses MCP)
• LLM clients — HTTP connection pools closed (only if the provider exposes close())

Without it, sockets may remain open until the garbage collector finalises the object, producing ResourceWarning noise in tests and connection leaks in long-running services.

The recommended pattern is the with statement — close() is called automatically on exit, even if compile() raises:

with Compiler(uri="path/to/your_graph.yml") as compiler:
    compiler.compile()
    outputs = compiler.get_outputs()

In unittest, use setUp / tearDown:

class TestMyGraph(unittest.TestCase):
    def setUp(self):
        self.compiler = Compiler(uri="path/to/your_graph.yml")

    def tearDown(self):
        self.compiler.close()

    def test_compile(self):
        self.compiler.compile()
        outputs = self.compiler.get_outputs()
        ...

Inspecting outputs

get_outputs() returns a CompiledOutput object:

outputs = compiler.get_outputs()

for node in outputs.nodes:
    print(f"[{node.node_id}]")
    if node.response.messages:
        for msg in node.response.messages:   # LLM text response (list of strings)
            print(msg)
    if node.response.json_output:
        print(node.response.json_output)     # structured JSON output
    print(node.compiled_time)                # seconds this node took
    if node.context_window:                  # context utilization (when context_window is set)
        pct = node.response.input_size / node.context_window * 100
        print(f"context: {node.response.input_size}/{node.context_window} ({pct:.1f}%)")

print(f"total time : {outputs.compile_time:.2f}s")
print(f"input tokens : {outputs.input_size}")
print(f"output tokens: {outputs.output_size}")

All executed nodes are included in outputs.nodes. The show flag on a node is a display hint used by save_outputs_as_markdown(); it does not filter what is returned by get_outputs().

Overriding the user message at runtime

The user_message defined in the YAML is the default. You can replace it before calling compile() to drive the same graph with different inputs:

with Compiler(uri="path/to/your_graph.yml") as compiler:
    compiler.user_message = "Explain the risks of nuclear energy."
    compiler.compile()

Defining tools in Python

LLMTool and LLMStructuredSchema are available at the top of the import tree:

from kegal import LLMTool
from kegal.llm import LLMStructuredSchema

Loading from a dict

If the graph is built programmatically rather than read from a file, pass a source dict instead of a URI:

graph_dict = {
    "models": [{"llm": "ollama", "model": "ministral-3:3b", "host": "http://localhost:11434"}],
    "user_message": "Hello",
    "prompts": [...],
    "nodes": [...],
    "edges": [...],
}
with Compiler(source=graph_dict) as compiler:
    compiler.compile()

For more advanced usage — attaching Python tool executors, MCP servers, fan-out/fan-in pipelines, guard nodes, RAG, and multi-provider graphs — see docs/tutorials.md.

CLI

After installation, the kegal command is available in your shell.

kegal --version          # print installed version
kegal run [path]         # run a project

Project layout

A KeGAL project is a folder containing a mandatory kegal.yml config file and your graph definition:

my_project/
├── kegal.yml
└── my_graph.yml

kegal.yml fields:

Unknown keys in kegal.yml are warned and ignored. Setting message/chunks with mode: once also warns.

once mode — runs the graph once using values from the YAML and exits:

# kegal.yml
graph: my_graph.yml
mode: once

chat mode — keeps a loop alive; prompts for user input on every turn until Ctrl+D:

# kegal.yml
graph: my_graph.yml
mode: chat
message: true
chunks: false

Configuration and runtime errors print a clean Error: … message and exit with code 1. In chat mode, per-turn errors print the message and continue the loop.

Running a project

# from inside the project folder
kegal run

# or specify the path
kegal run path/to/my_project

Features

• Graph-based workflows – define multi-node agent pipelines in YAML or JSON
• Fan-out / fan-in edges – children launches parallel sub-tasks; fan_in aggregates multiple branches before continuing; both are recursive and composable
• Multi-board blackboard pipeline – multiple named shared markdown boards (GraphBlackboard) written and read across nodes; Cat-1 writers seed a board, Cat-2 enrichers extend it in parallel, Cat-3 readers consume the final result. Boards support import chains (prepend another board's content at read time) and cleanup control (truncate at init or preserve existing content). Execution order is inferred automatically from blackboard.read/write flags even with flat edge declarations.
• ReAct loop – controller node iteratively reasons and dispatches to specialist agent nodes until it signals done: true; supports automatic conversation compaction (compact: true) for long loops; controller output flows to downstream nodes via message_passing like any regular node
• Structured output – enforce JSON schemas on LLM responses. On AWS Bedrock (llm: "bedrock") this uses Bedrock's native structured-output API, which requires a model that supports it (Anthropic Claude 4.5 or a recent open-weight model such as Kimi/Moonshot, Qwen, DeepSeek, Mistral); Claude 3.x and Amazon Nova are not supported for structured output
• Validation gate – nodes with a validation boolean field in their structured output act as guards: when the LLM returns validation: false, the graph execution stops immediately, preventing downstream nodes from running. Useful for content moderation and prompt injection prevention.
• Message passing – forward node outputs to downstream nodes; ordering inferred automatically from flags and declaration order — no explicit edge required for linear pipelines
• Verbose logging – set verbose: true on the graph to get a colored INFO-level trace on stderr: compile start/done with token totals, per-node start/end with elapsed time and token counts, each tool call ([mcp]/[py] tagged) with parameters and result preview, and the full ReAct loop trace. ANSI colors are applied automatically on TTY terminals and suppressed on pipes/redirects
• MCP support – connect nodes to external tool servers via the Model Context Protocol (stdio and SSE transports)
• Python tool executors – attach plain Python callables as tools without running a separate process
• Multi-provider support – use different LLMs in the same graph
• Context window tracking – declare context_window on a model to get accurate resume compaction thresholds and per-node context-utilization percentages in markdown output
• Chat history – maintain conversational context across nodes; scopes can be inline arrays or external JSON files with optional auto: true to let KeGAL append user+assistant turns automatically after each compile() call
• RAG support – inject retrieved document chunks into prompts
• Prompt validation – at Compiler() construction, placeholder tokens in every prompt template are checked against the node config; misconfigurations are reported as warnings before the first compile() call
• Safe resource cleanup – compiler.close() releases MCP server processes and LLM HTTP connection pools; idempotent and transport-aware

Supported LLM Providers

• Anthropic - Direct API (kegal[anthropic])
• OpenAI - GPT models (kegal[openai])
• Google Gemini - Gemini models (kegal[gemini])
• Ollama - Local LLM hosting (kegal[ollama])
• AWS Bedrock - Amazon Nova, Anthropic, and open-weight models (Kimi/Moonshot, Qwen, DeepSeek, Mistral, …) via the Bedrock Converse API (kegal[aws]). Structured output uses Bedrock's native outputConfig API — supported on Claude 4.5 and recent open-weight models, not on Claude 3.x / Nova.

Copyright

Copyright 2025 by Kedos srl.

This software is released under the MIT license.