diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3aa860b..c64523a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,18 @@
 
 All notable changes to the Toolpath workspace are documented here.
 
+## Derive: recognize camelCase file-path tool fields — 2026-07-09
+
+- **`toolpath-convo`** (0.11.3): the shared `derive_path` file-path
+  extractor now probes the camelCase siblings `filePath` and `fileName`
+  in addition to `file_path`/`filename`/`path`/`file`. Providers that
+  leave file-mutation synthesis to the shared derive (rather than
+  pre-building `Turn.file_mutations`) previously dropped a `FileWrite`
+  tool's artifact when its input used the camelCase convention (e.g.
+  opencode's `filePath`). snake_case is probed first, so existing inputs
+  resolve unchanged. Additive; no effect on already-derived documents.
+  Follow-up to the change-key relativization work (0.11.2).
+
 ## Derive: relativize file change keys against `path.base` — 2026-07-08
 
 - **`toolpath-convo`** (0.11.2): `derive_path` now stores file-change
diff --git a/Cargo.lock b/Cargo.lock
index cfb3faf..f176c72 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3924,7 +3924,7 @@ dependencies = [
 
 [[package]]
 name = "toolpath-convo"
-version = "0.11.2"
+version = "0.11.3"
 dependencies = [
  "chrono",
  "jsonschema",
diff --git a/Cargo.toml b/Cargo.toml
index f0dfbde..1823903 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,7 +24,7 @@ license = "Apache-2.0"
 
 [workspace.dependencies]
 toolpath = { version = "0.7.0", path = "crates/toolpath" }
-toolpath-convo = { version = "0.11.2", path = "crates/toolpath-convo" }
+toolpath-convo = { version = "0.11.3", path = "crates/toolpath-convo" }
 toolpath-git = { version = "0.6.0", path = "crates/toolpath-git" }
 toolpath-claude = { version = "0.12.0", path = "crates/toolpath-claude", default-features = false }
 toolpath-gemini = { version = "0.6.0", path = "crates/toolpath-gemini", default-features = false }
diff --git a/crates/toolpath-convo/Cargo.toml b/crates/toolpath-convo/Cargo.toml
index e78e99e..c788053 100644
--- a/crates/toolpath-convo/Cargo.toml
+++ b/crates/toolpath-convo/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "toolpath-convo"
-version = "0.11.2"
+version = "0.11.3"
 edition.workspace = true
 license.workspace = true
 repository = "https://github.com/empathic/toolpath"
diff --git a/crates/toolpath-convo/src/derive.rs b/crates/toolpath-convo/src/derive.rs
index 134f0e8..9ed133f 100644
--- a/crates/toolpath-convo/src/derive.rs
+++ b/crates/toolpath-convo/src/derive.rs
@@ -591,7 +591,9 @@ pub(crate) fn relativize_key(path: &str, base_uri: Option<&str>) -> String {
 }
 
 fn extract_file_path(tool: &ToolInvocation) -> Option<String> {
-    for field in &["file_path", "path", "filename", "file"] {
+    // snake_case first so existing inputs resolve unchanged; camelCase
+    // siblings (`filePath`, `fileName`) cover conventions like opencode's.
+    for field in &["file_path", "filePath", "path", "filename", "fileName", "file"] {
         if let Some(v) = tool.input.get(*field)
             && let Some(s) = v.as_str()
         {
@@ -1251,6 +1253,27 @@ mod tests {
         assert!(path.steps[0].change.contains_key("c.rs"));
     }
 
+    #[test]
+    fn test_tool_use_filewrite_with_camelcase_file_path_field() {
+        // camelCase `filePath` is opencode's tool-input convention; a
+        // provider that leaves file-mutation synthesis to the shared
+        // derive would otherwise drop the artifact entirely.
+        let mut turn = base_turn("t1", Role::Assistant);
+        turn.tool_uses = vec![fw_tool("write", "tu1", serde_json::json!({"filePath": "d.rs"}))];
+        let view = view_with(vec![turn]);
+        let path = derive_path(&view, &DeriveConfig::default());
+        assert!(path.steps[0].change.contains_key("d.rs"));
+    }
+
+    #[test]
+    fn test_tool_use_filewrite_with_camelcase_file_name_field() {
+        let mut turn = base_turn("t1", Role::Assistant);
+        turn.tool_uses = vec![fw_tool("W", "tu1", serde_json::json!({"fileName": "e.rs"}))];
+        let view = view_with(vec![turn]);
+        let path = derive_path(&view, &DeriveConfig::default());
+        assert!(path.steps[0].change.contains_key("e.rs"));
+    }
+
     #[test]
     fn test_tool_use_filewrite_no_recognized_field() {
         let mut turn = base_turn("t1", Role::Assistant);
diff --git a/site/_data/crates.json b/site/_data/crates.json
index 4e0ca01..37899b3 100644
--- a/site/_data/crates.json
+++ b/site/_data/crates.json
@@ -9,7 +9,7 @@
   },
   {
     "name": "toolpath-convo",
-    "version": "0.11.2",
+    "version": "0.11.3",
     "description": "Provider-agnostic conversation types, traits, and Toolpath-Path derivation",
     "docs": "https://docs.rs/toolpath-convo",
     "crate": "https://crates.io/crates/toolpath-convo",