Understanding Skills and Tools
Agents use tools to take actions in the world — search the web, send messages, read files, manage schedules, and more. Tools are pieces of code that actually do things. When an agent decides it needs to look something up online, it calls theweb_search tool. When it needs to create a file, it
calls the write tool. Tools are the hands of your agent.
Skills are different. They are custom instructions you write to teach
agents new behaviors. A skill might define a customer support persona, a code
review checklist, or a set of rules for moderating a community. Skills are
knowledge that guides how your agent thinks and responds — they shape its
personality, its expertise, and its approach to problems.
Together, tools give your agents capabilities and skills give them expertise.
An agent with the right tools can do almost anything; an agent with the right
skills knows exactly how to do it.
The Four Types
Comis organizes all agent capabilities into four categories. Each serves a different purpose and comes from a different source:| Type | What It Is | Examples | Who Creates It |
|---|---|---|---|
| Built-in Tools | Core tools for file operations, web access, and shell commands | read, write, exec, web_search, browser | Comes with Comis |
| Platform Tools | Comis-specific tools for messaging, scheduling, and administration | cron, message, sessions_spawn, gateway | Comes with Comis |
| Prompt Skills | Custom Markdown instruction files that teach agents new behaviors | Customer support persona, code review checklist | You create these |
| MCP Tools | External tools from MCP (Model Context Protocol) servers | Database queries, third-party APIs, custom integrations | External servers |
Built-in Tools
The “built-in tools” page covers the foundational tools that ship with every Comis agent — file operations, shell execution, web access, and browser automation. These are the lowest layer in the tool stack: any agent built on the underlying coding-agent framework gets them out of the box.- File operations — read, write, edit, search files; apply patches; edit Jupyter notebooks
- Shell commands — execute commands and manage background processes inside an OS-level sandbox
- Web access — search the web (8 providers) and fetch page content
- Browser automation — control a headless Chromium browser (16 actions)
- Context tools — search and recall content from the current session or the compressed context DAG
exec turned off while
keeping everything else.
See Built-in Tools for the complete reference with
parameters and usage examples.
Across built-in tools and platform tools combined, Comis ships 70 tools
in total. The 70 break down across functional categories: web (2), files (7),
apply_patch (1), exec/process (2), terminal driver (9), memory (5 including
opt-in memory_ask), sessions (6), agents (4 including pipeline), messaging (6),
scheduling (1), media (6), infrastructure/context (4 + 4 context-DAG), and
fleet admin (8). See Built-in Tools and
Platform Tools for the per-category breakdown.
Platform Tools
Platform tools are specific to Comis. There are tools across categories including:- Scheduling — create cron jobs and manage heartbeat timing
- Messaging — send, reply, react, edit, and delete messages across any connected channel
- Sessions — manage conversations, spawn sub-agents, run pipelines
- Media — analyze images, generate speech, transcribe audio, process documents
- Infrastructure — read and modify configuration at runtime
- Memory — search, read, and store long-term memories
- Fleet management — supervisor-level tools for managing the entire installation
- Platform actions — platform-specific moderation for Discord, Telegram, Slack, and WhatsApp
Prompt Skills
Prompt skills are Markdown files (with a specialSKILL.md format) that you
write to teach your agents new behaviors. No coding required — you write
instructions in plain language, and Comis loads them into the agent’s context.
A prompt skill might define:
- A customer support persona with tone guidelines and escalation procedures
- A set of moderation rules for a Discord community
- A research methodology that the agent follows step by step
- A code review checklist with specific criteria to check
MCP Tools
MCP (Model Context Protocol) is an open standard that lets AI agents connect to external tool servers. If someone has built an MCP server for a database, a CRM, a project management tool, or any other service, your Comis agents can use those tools directly. This is how you extend Comis with capabilities from the broader AI ecosystem without writing any code yourself. Comis connects to MCP servers over standard I/O or HTTP, discovers available tools automatically, and makes them available to your agents alongside built-in and platform tools. See MCP Integration for setup instructions.How Tools Get Selected
Not every agent needs every tool. Comis lets you configure a tool policy for each agent, controlling exactly which tools it can access. Think of it like giving each agent a specific toolbox: a coding agent might have file and shell tools, while a customer service agent might have only messaging tools. Comis ships with five named profiles plus two specialised “minimal” presets for non-interactive runs, so you can quickly set the right level of access:- minimal —
read+write, for highly restricted agents - coding — file operations, shell, and process management for development agents
- messaging —
message+session_statusfor communication-focused agents - supervisor — fleet-management tools for administration agents
- full — all tools with no restrictions (this is the default)
- cron-minimal — safe subset for scheduled cron jobs (web, message, basic file/memory, cron itself)
- heartbeat-minimal — even narrower subset for periodic agent heartbeats
Explore Skills
Built-in Tools
File operations, shell commands, web search, and browser automation
Platform Tools
Messaging, scheduling, sessions, media, and administration tools
Prompt Skills
Write custom instruction files to teach agents new behaviors
MCP Integration
Connect to external tool servers using the Model Context Protocol
Tool Policy
Control which tools each agent can use
Agent Tools
See every platform tool in action — the master reference for all
Comis-specific tools
