Tool registry - Voss Docs

The harness exposes a local tool registry. Each tool is classified as read-only or mutating so permission modes can make reliable decisions. Each entry is a capability in the broader registry — it also declares a group, network usage, scope requirements, and audit behavior. Roles grant capabilities by group, and the full normalized schema lives in the Capabilities reference.

Tool classes

Tool	Class	Purpose
`fs_read`	Read-only	Read files and directory summaries
`fs_glob`	Read-only	Find files by glob pattern
`fs_grep`	Read-only	Search file contents
`git_status`	Read-only	Inspect working tree state
`git_diff`	Read-only	Inspect diffs
`voss_check`	Read-only	Run Voss checks
`code_recall`	Read-only	Search code and project memory for concept-level questions
`fs_write`	Mutating	Write a file
`fs_edit`	Mutating	Patch an existing file
`shell_run`	Mutating	Run an allowlisted shell command

Diff previews

File write tools produce a diff preview before permission decisions. This keeps risky changes inspectable before approval.

View tools locally

voss tools

The command shows registered tools and whether each one mutates state.

Tool mutability is data in the registry. Voss should not infer safety from a tool name alone. Inspect the full capability surface with voss capabilities list and voss capabilities inspect <name>.

SessionsList and resume Voss harness sessions.

​Tool classes

​Diff previews

​View tools locally

Tool classes

Diff previews

View tools locally