Fawx ships with 13+ built-in tools. The model calls them natively through provider function-calling APIs. No prompt engineering required.
When the AI model decides it needs to take an action (read a file, search the web, run a command), it emits a structured tool call. Fawx executes the tool, checks permissions, and returns the result to the model. This can happen multiple times in a single response.
Tools are subject to the capability-based permission system. If a tool call falls outside the agent's boundaries, it receives a structured denial explaining what happened and why.
Read the contents of a file. Supports text files and common binary formats. Large files are chunked automatically.
Create or overwrite a file. Creates parent directories automatically.
Make precise edits to a file by specifying the exact text to find and replace. Safer than full file writes for targeted changes.
List the contents of a directory with file sizes and types.
Execute shell commands. Supports background processes, timeouts, and working directory specification. Output is captured and returned to the model.
Search the web using Brave Search. Returns titles, URLs, and snippets.
Fetch a URL and extract readable content as markdown or text. Handles HTML, PDFs, and other common formats.
Control a headless browser for complex web interactions. Navigate, click, type, take screenshots, and extract page content.
Check the current repository status: branch, staged changes, untracked files.
View diffs for staged or unstaged changes, or between commits.
Stage files and create commits with a message.
Read from the agent's structured memory. Memories persist across sessions and are stored locally.
Write observations and learnings to structured memory for future reference.
Beyond built-in tools, Fawx supports WASM skill plugins that add new capabilities. Skills are loaded at runtime, sandboxed, and cryptographically signed. See the Skills docs for details.
A typical multi-step interaction:
shell to run grep -rn TODO src/write_file to create TODO-summary.mdEach step is visible in the conversation. The model decides which tools to call, and Fawx handles execution, error recovery, and retries.