Built-in tools available to agents beyond the standard file and shell operations.
Slim only intercepts apply_patch before the native tool runs. It rewrites recoverable stale patches, canonizes safe tolerant matches against the real file when unicode/trim drift is the only mismatch, keeps the authored new_lines bytes intact, preserves the existing file EOL/final-newline state for updates, validates malformed patches strictly before helper execution, uses a conservative bounded LCS fallback, accumulates helper state when the same path appears in multiple Update File hunks, blocks apply_patch before native execution if any patch path falls outside the allowed root/worktree, and fails on ambiguity instead of guessing. It does not rewrite edit or write inputs.
Fetch remote pages with content extraction tuned for docs/static sites.
| Tool | Description |
|---|---|
webfetch |
Fetch a URL, optionally prefer llms.txt, extract main content from HTML, include metadata, and optionally save binary responses |
webfetch blocks cross-origin redirects unless the requested URL or derived permission patterns explicitly allow them, and it can fall back to the raw fetched content when secondary-model summarization is unavailable.
Fast, structural code search and refactoring — more powerful than plain text grep.
| Tool | Description |
|---|---|
grep |
Fast content search using ripgrep |
ast_grep_search |
AST-aware code pattern matching across 25 languages |
ast_grep_replace |
AST-aware code refactoring with dry-run support |
ast_grep understands code structure, so it can find patterns like "all arrow functions that return a JSX element" rather than relying on exact text matching.
OpenCode automatically formats files after they are written or edited, using language-specific formatters. No manual step needed.
Includes Prettier, Biome, gofmt, rustfmt, ruff, and 20+ others.
See the official OpenCode docs for the complete list.
Auto-continue has its own guide now:
- Todo Continuation — controls, safety gates, behavior, and config