Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add agents/jetbrains/koog/indexgit clone --depth 1 https://github.com/JetBrains/koogWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00000 | $0.01459 |
| Opus 5 | $0.00000 | $0.00730 |
| Sonnet 5 | $0.00000 | $0.00292 |
| Haiku 4.5 | $0.00000 | $0.00146 |
Grade A, and why
index scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 170 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Agents
AI agents are autonomous systems that can reason, make decisions, interact with the environment, and take actions to achieve a specific goal. In Koog, an AI agent is more than just a wrapper around an LLM; it is a structured, type-safe state machine designed for the JVM ecosystem.
Koog agents are built around the following core concepts:
- A prompt executor manages and executes prompts, enabling the agent to interact with LLMs for reasoning and decision-making.
- A strategy defines the agent's workflow. It can be in the form of a directed graph, a function, or a planner. See Agent types.
- An agent can use tools to interact with external data sources and services.
- You can extend and enhance the functionality of AI agents using features.
!!! tip
For information about creating and running a minimal agent, see [Quickstart](../quickstart.md).
Agent types
Depending on the task you need to perform, Koog provides several agent types:
- Basic agents are ideal for simple tasks that don't require any custom logic. These agents implement a predefined strategy that works for most common use cases.
- Graph-based agents provide full control and flexibility of the agent's workflow, state management, and visualization.
- Functional agents enable you to quickly prototype custom logic as a function with access to the agent's context.
- Planner agents can autonomously plan and execute multistep tasks through iterative cycles until they reach a desired final state.
Agent configuration
Agent configuration defines the agent's execution parameters, including the initial prompt, language model, and iteration limits.
!!! tip
For information about creating and running a minimal agent, see [Quickstart](../quickstart.md).
For simple agents, besides the mandatory prompt executor and language model, you can specify the initial system prompt and some other parameters directly in the agent constructor:
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- yesterday First seen · 170 lines · 0 tokens per session scan A 2e7280cbddb5
index is an agent published in the GitHub repository JetBrains/koog (4,541 stars, last pushed 3d ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 1,459 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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