Move the config schema generator into a dedicated crate (#41915)

## What changed

- Add the `codex-config-schema` workspace and Bazel crate for the
  `codex-write-config-schema` binary.
- Preserve `codex-rs/core/config.schema.json` as the default output location.
- Update `just write-config-schema` to run the new crate and remove the schema
  generator's `clap` dependency and binary target from `codex-core`.

GitOrigin-RevId: 7447f97d6e44d1077b16d2d850f8a8add9117ea6

codex-rs/Cargo.lock

@@ -2703,6 +2703,15 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "codex-config-schema"
+version = "0.0.0"
+dependencies = [
+ "anyhow",
+ "clap",
+ "codex-config",
+]
+
 [[package]]
 name = "codex-connectors"
 version = "0.0.0"
@@ -2759,7 +2768,6 @@ dependencies = [
  "base64 0.22.1",
  "bm25",
  "chrono",
- "clap",
  "codex-agent-graph-store",
  "codex-agent-roles",
  "codex-analytics",

codex-rs/Cargo.toml

@@ -36,6 +36,7 @@ members = [
     "collaboration-mode-templates",
     "connectors",
     "config",
+    "config-schema",
     "context-fragments",
     "shell-command",
     "shell-escalation",

codex-rs/config-schema/BUILD.bazel

@@ -0,0 +1,6 @@
+load("//:defs.bzl", "codex_rust_crate")
+
+codex_rust_crate(
+    name = "config-schema",
+    crate_name = "codex_config_schema",
+)

codex-rs/config-schema/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "codex-config-schema"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+
+[[bin]]
+name = "codex-write-config-schema"
+path = "src/main.rs"
+
+[lints]
+workspace = true
+
+[dependencies]
+anyhow = { workspace = true }
+clap = { workspace = true, features = ["derive"] }
+codex-config = { workspace = true }

codex-rs/config-schema/src/main.rs

@@ -1,3 +1,5 @@
+//! Generates the canonical config schema fixture for development and releases.
+
 use anyhow::Result;
 use clap::Parser;
 use std::path::PathBuf;
@@ -12,9 +14,9 @@ struct Args {
 
 fn main() -> Result<()> {
     let args = Args::parse();
-    let out_path = args
-        .out
-        .unwrap_or_else(|| PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("config.schema.json"));
+    let out_path = args.out.unwrap_or_else(|| {
+        PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("../core/config.schema.json")
+    });
     codex_config::schema::write_config_schema(&out_path)?;
     Ok(())
 }

codex-rs/core/Cargo.toml

@@ -8,10 +8,6 @@ version.workspace = true
 name = "codex_core"
 path = "src/lib.rs"
 
-[[bin]]
-name = "codex-write-config-schema"
-path = "src/bin/config_schema.rs"
-
 [lints]
 workspace = true
 
@@ -22,7 +18,6 @@ async-channel = { workspace = true }
 base64 = { workspace = true }
 bm25 = { workspace = true }
 chrono = { workspace = true, features = ["serde"] }
-clap = { workspace = true, features = ["derive"] }
 codex-analytics = { workspace = true }
 codex-agent-graph-store = { workspace = true }
 codex-agent-roles = { workspace = true }

justfile

@@ -175,7 +175,7 @@ mcp-server-run *args:
 
 # Regenerate the json schema for config.toml from the current config types.
 write-config-schema:
-    cargo run -p codex-core --bin codex-write-config-schema
+    cargo run -p codex-config-schema --bin codex-write-config-schema
 
 # Regenerate vendored app-server protocol schema artifacts.
 write-app-server-schema *args: