feat(tools): ast-grep structural search/rewrite and gh CLI operations

README.md

@@ -133,6 +133,8 @@ crash-recoverable and inspectable from the CLI the whole way.
 | `read_file` | One path for files (hashline `line#hash` anchors), directories (sorted listings), and http(s) URLs (streamed cap; refused when the sandbox denies network) |
 | `write_file` / `edit_file` | Writes under sandbox confinement; edits by exact string or by anchored hashline patch with stale-anchor recovery |
 | `grep` / `glob` | Regex content search and path patterns, `.gitignore`-aware |
+| `ast_grep` / `ast_edit` | Structural search and rewrite over the syntax tree via [ast-grep](https://ast-grep.github.io) (when installed); rewrites preview by default and write only on `apply: true` |
+| `github` | GitHub CLI operations with your own `gh` login (when installed) — reads run in parallel, mutations stay serial |
 | `agent` | The pen: delegate to durable child agents (above) |
 | `job` | The coordination plane: list children with live state, wait for a result, cancel a background child |
 | `todo` | A durable session plan in the store — survives crashes and resumes; one item in progress at a time, enforced by the runtime |

crates/cli/src/main.rs

@@ -598,6 +598,9 @@ async fn run(
         Store::default_path(),
         &session.id,
     )));
+    // GitHub, with the user's own gh login. Top-level runs only — pen
+    // children keep to the workspace unless the coordinator acts itself.
+    registry.register(std::sync::Arc::new(bullpen_tools::GitHub::new()));
     // Follow-up questions reach the terminal only when someone is on it;
     // otherwise the detached variant answers with the reason instead.
     let interactive = !json && std::io::IsTerminal::is_terminal(&std::io::stdin());

crates/harness/src/pen.rs

@@ -32,7 +32,7 @@ use std::time::Duration;
 use bullpen_agent::{Agent, AgentConfig};
 use bullpen_llm::{Provider, Role, ToolSpec};
 use bullpen_store::{Session, SessionWorker, Store};
-use bullpen_tools::{Glob, Grep, ReadFile, Registry, Tool, ToolCtx, ToolError};
+use bullpen_tools::{AstGrep, Glob, Grep, ReadFile, Registry, Tool, ToolCtx, ToolError};
 use serde_json::{Value, json};
 
 use crate::{StoreJournal, prepare_session, worktree};
@@ -187,6 +187,7 @@ fn registry_for_mode(mode: &str) -> Result<Registry, ToolError> {
             r.register(Arc::new(ReadFile));
             r.register(Arc::new(Grep));
             r.register(Arc::new(Glob));
+            r.register(Arc::new(AstGrep::new()));
             Ok(r)
         }
         // Full workspace tools — still no nested pen.