docs: RFC for JSONL streaming format

RFC.md

@@ -103,6 +103,23 @@ the inner fields.
 PascalCase variant names visually distinguish the type tag from the lowercase
 structural fields inside (`step`, `path`, `graph`).
 
+### File Extensions
+
+Toolpath documents use a two-part extension encoding the document type and
+serialization format:
+
+| Extension | Document type | Description |
+| --------- | ------------- | ----------- |
+| `.path.json` | Path (canonical) | A complete `{"Path": {...}}` JSON document. |
+| `.path.jsonl` | Path (streaming) | A line-oriented JSONL stream that seals to a `Path`. See the [JSONL Streaming RFC](docs/RFC-jsonl.md). |
+
+`Step` and `Graph` documents use plain `.json` files with the appropriate
+`{"Step": ...}` or `{"Graph": ...}` envelope. Only `Path` has a streaming
+peer format.
+
+Graph `$ref` entries MUST point to sealed `.path.json` files, not to
+`.path.jsonl` streams.
+
 ### ID Uniqueness
 
 IDs must be unique within their containing scope:

crates/toolpath-claude/src/derive.rs

@@ -95,15 +95,16 @@ pub fn derive_path(conversation: &Conversation, config: &DeriveConfig) -> Path {
             Some(MessageContent::Parts(parts)) => {
                 for part in parts {
                     match part {
-                        ContentPart::Text { text } => {
-                            if !text.trim().is_empty() {
-                                text_parts.push(text.clone());
-                            }
+                        ContentPart::Text { text }
+                            if !text.trim().is_empty() =>
+                        {
+                            text_parts.push(text.clone());
                         }
-                        ContentPart::Thinking { thinking, .. } => {
-                            if config.include_thinking && !thinking.trim().is_empty() {
-                                text_parts.push(format!("[thinking] {}", thinking));
-                            }
+                        ContentPart::Thinking { thinking, .. }
+                            if config.include_thinking
+                                && !thinking.trim().is_empty() =>
+                        {
+                            text_parts.push(format!("[thinking] {}", thinking));
                         }
                         ContentPart::ToolUse { name, input, .. } => {
                             tool_uses.push(name.clone());
@@ -127,12 +128,10 @@ pub fn derive_path(conversation: &Conversation, config: &DeriveConfig) -> Path {
                     }
                 }
             }
-            Some(MessageContent::Text(text)) => {
-                if !text.trim().is_empty() {
-                    text_parts.push(text.clone());
-                }
+            Some(MessageContent::Text(text)) if !text.trim().is_empty() => {
+                text_parts.push(text.clone());
             }
-            None => {}
+            _ => {}
         }
 
         // Skip entries with no conversation content and no file changes

crates/toolpath-claude/src/io.rs

@@ -58,7 +58,7 @@ impl ConvoIO {
             }
         }
 
-        metadata.sort_by(|a, b| b.last_activity.cmp(&a.last_activity));
+        metadata.sort_by_key(|m| std::cmp::Reverse(m.last_activity));
         Ok(metadata)
     }
 

crates/toolpath-claude/src/lib.rs

@@ -240,7 +240,7 @@ impl ClaudeConvo {
             }
         }
 
-        metadata.sort_by(|a, b| b.last_activity.cmp(&a.last_activity));
+        metadata.sort_by_key(|m| std::cmp::Reverse(m.last_activity));
         Ok(metadata)
     }
 
@@ -316,7 +316,7 @@ impl ClaudeConvo {
             }
         }
 
-        conversations.sort_by(|a, b| b.last_activity.cmp(&a.last_activity));
+        conversations.sort_by_key(|c| std::cmp::Reverse(c.last_activity));
         Ok(conversations)
     }