fix(cli): Preserve conversation config clears

crates/jp_cli/src/config_pipeline.rs

@@ -323,6 +323,12 @@ impl ConfigPipeline {
         unsets: &[String],
     ) -> Result<PartialAppConfig> {
         let mut partial = conversation.fill_from(self.base.clone());
+        if !unsets.is_empty() {
+            debug!(
+                ?unsets,
+                "Conversation clears suppressing base-layer values."
+            );
+        }
         for path in unsets {
             if let Err(error) = partial.unset(path) {
                 warn!(%path, %error, "Ignoring a config delta unset for an unknown field.");

crates/jp_conversation/src/stream.rs

@@ -233,11 +233,12 @@ impl ConversationStream {
         Ok(partial)
     }
 
-    /// Dotted config paths explicitly cleared and not subsequently set.
+    /// Dotted config paths explicitly cleared and still absent from the
+    /// accumulated state.
     ///
     /// Reset deltas discard earlier clears.
-    /// A clear followed by a replacement in the same apply delta is not
-    /// included.
+    /// A path the accumulated state holds a value at is not included, whether
+    /// the value arrived in the clearing delta or a later one.
     /// Unknown paths are ignored.
     ///
     /// # Errors
@@ -252,6 +253,12 @@ impl ConversationStream {
             }
         }
 
+        // Nothing cleared means nothing to probe, and the fold below is a full
+        // merge per delta in the stream.
+        if unsets.is_empty() {
+            return Ok(Vec::new());
+        }
+
         let partial = self.config_partial()?;
         Ok(unsets
             .into_iter()

crates/jp_conversation/src/stream_tests.rs

@@ -187,6 +187,18 @@ fn a_delta_that_only_clears_is_recorded() {
     assert!(resolved_arguments(&stream).is_empty());
 }
 
+/// A stream that never cleared anything reports nothing, deltas or not.
+#[test]
+fn config_unsets_is_empty_without_a_clearing_delta() {
+    let mut stream = stream_with_server(&["serve"]);
+    stream.add_config_delta(ApplyDelta::new(
+        delta_timestamp(),
+        server_arguments_partial(&["run"]),
+    ));
+
+    assert!(stream.config_unsets().unwrap().is_empty());
+}
+
 #[test]
 fn config_unsets_keeps_clears_across_unrelated_deltas() {
     let mut stream = stream_with_server(&["serve"]);

docs/.vitepress/rfd-summaries.json

@@ -292,7 +292,7 @@
     "summary": "UPPERCASE keywords NONE and WORKSPACE reset config state; loader.reset entry setting provides local resets; ConfigDelta becomes enum to persist resets."
   },
   "079-config-sources-and-load-order.md": {
-    "hash": "f6dc6f90d9a17bd469d82db2b8c4998f43cd8d126e774dc117cc4a9337978321",
+    "hash": "1a9ca633586e826b8ecd5a44d5412e811eb26c3515d270a97c43b9b88e93e7fe",
     "summary": "JP loads config from four implicit sources plus environment variables, with extends directives and inherit flags controlling precedence."
   },
   "074-eager-loading-with-command-declared-data-requirements.md": {

docs/configuration.md

@@ -225,6 +225,23 @@ Set configuration in conversation <conversation id>
 This appends a delta to the conversation's event stream, leaving earlier turns
 untouched.
 
+An option is cleared by querying with it set to `null`:
+
+```bash
+$ jp query --id <conversation id> --cfg assistant.name:=null "..."
+```
+
+A cleared option stays cleared for the rest of the conversation.
+Later turns run without it even when a configuration file sets that option.
+The conversation records the option as empty, and the file layer cannot fill it
+back in.
+
+Two things retire a clear:
+
+- Setting a value at the same path, such as `--cfg assistant.name=Bot`.
+- A reset (`--cfg=WORKSPACE`), which discards everything the conversation
+  accumulated, including its clears.
+
 To edit the files directly, use `jp conversation edit`:
 
 ```bash

docs/rfd/079-config-sources-and-load-order.md

@@ -255,6 +255,9 @@ init`), the sequence is:
 11. The result is the **base partial** for this invocation.
 12. Load the conversation's `base_config.json` and event-stream `ConfigDelta`s
     (for continuing or forking invocations only).
+    A path those deltas cleared and never set again ([RFD 070]) is also cleared
+    from the base partial, so the file layer cannot restore it.
+    Step 13 can set it again.
 13. Apply `--cfg` and `--no-cfg` ([RFD 038]) directives left-to-right ([RFD
     008]).
 14. Apply CLI shortcut flags (`--model`, `--reasoning`, etc.).
@@ -278,6 +281,7 @@ pipeline may care about; see `ConfigPipeline::partial_without_conversation` and
   `config_load_paths` resolution across roots.
 - [RFD 054]: Split Conversation Config and Events — how `base_config.json` and
   event-stream `ConfigDelta`s are structured.
+- [RFD 070]: Negative Config Deltas — how a delta records a cleared path.
 - `crates/jp_cli/src/lib.rs` — `load_partial_configs_from_files` and
   `load_base_partial`.
 - `crates/jp_config/src/util.rs` — `load_partials_with_inheritance`,
@@ -290,4 +294,5 @@ pipeline may care about; see `ConfigPipeline::partial_without_conversation` and
 [RFD 035]: 035-multi-root-config-load-path-resolution.md
 [RFD 038]: 038-config-reset-keywords.md
 [RFD 054]: 054-split-conversation-config-and-events.md
+[RFD 070]: 070-negative-config-deltas.md
 [RFD 080]: 080-editor-as-a-config-source.md

docs/ticket/0kwgjda-no-surface-lists-the-config-options-a-conversation-has-clear.md

@@ -0,0 +1,51 @@
+# No surface lists the config options a conversation has cleared
+
+- **Status**: Todo
+- **Kind**: Feature
+- **Authors**: jp
+- **Date**: 2026-09-16
+- **Label**: client=cli
+- **Label**: domain=conversation
+- **Label**: package=jp_cli
+- **Label**: type=enhancement
+
+A conversation can clear a config option (`jp query --cfg
+assistant.name:=null`), and the clear holds for the rest of the conversation:
+the file layer cannot restore the option, because the pipeline reapplies the
+stream's cleared paths after filling from the base.
+
+Nothing reports which paths a conversation currently holds clear.
+
+`jp config show` resolves the file, env, and `--cfg` layers only —
+`Commands::Config(_)` returns an empty conversation layer
+(`crates/jp_cli/src/cmd.rs:200-207`), and `cmd/config/show.rs` never touches a
+conversation.
+So the option reads as absent, with no indication that a conversation-level
+clear is what holds it there.
+The only trace is the `unsets` array inside the stored event stream, reachable
+through `jp conversation edit --events`.
+
+The named input: a user clears `assistant.name` in a conversation, sets
+`assistant.name` in `.jp/config.toml` a week later, and has no way to find out
+why that conversation ignores it.
+`RUST_LOG=debug` logs the suppressed paths at the moment they apply, which helps
+a user who already suspects the cause, but no read surface answers the question
+directly.
+
+## Shape
+
+Two candidates, not exclusive:
+
+- Teach `jp config show` to apply the conversation layer when given `--id`, and
+  mark cleared paths distinctly from unset ones.
+- Report them in `jp conversation show`, alongside the conversation's other
+  stored state.
+
+`ConversationStream::config_unsets()` already computes this list, so either
+surface is a read away.
+
+Related: [RFD 060] (Config Explain) would subsume this if it lands first — a
+per-field provenance display answers "what is holding this field empty?" as a
+special case.
+
+[RFD 060]: https://jp.computer/rfd/060

docs/ticket/0kwgqkx-jp-config-set-reports-success-for-a-clear-it-never-records.md

@@ -0,0 +1,60 @@
+# jp config set reports success for a clear it never records
+
+- **Status**: Todo
+- **Kind**: Bug
+- **Authors**: jp
+- **Date**: 2026-09-16
+- **Label**: client=cli
+- **Label**: domain=conversation
+- **Label**: package=jp_cli
+- **Label**: type=bug
+
+`jp config set --id <id> --cfg assistant.name:=null` prints `Set configuration
+in conversation <id>` and records nothing.
+The same argument through `jp query` records a delta whose `unsets` holds
+`assistant.name`, and the option stays cleared for the rest of the conversation.
+
+## Why
+
+`Set::run` builds its payload with
+`config_pipeline::build_partial_from_cfg_args`
+(`crates/jp_cli/src/cmd/config/set.rs:28`), which applies the arguments onto
+`PartialAppConfig::empty()` (`config_pipeline.rs:578`).
+A `:=null` assignment clears a field, so clearing a field of an already-empty
+partial produces an empty partial: the payload carries no trace of what the user
+asked to clear.
+
+`override_to_record` then merges that empty partial onto the conversation's
+accumulated state, resolves both sides, finds them equal, and returns `None`
+(`config_pipeline.rs:64-78`), so no `ConfigDelta` is appended.
+The success line is printed unconditionally afterwards (`set.rs:68-69`).
+
+The file target has the same hole: `set_in_file` merges the empty partial into
+the config file and writes it back unchanged (`set.rs:85-90`).
+
+A partial cannot express "cleared" — that is what `ApplyDelta::unsets` exists
+for ([RFD 070]).
+The query path reaches it through `turn_config_delta`/`delta_with_unsets`
+(`cmd/query.rs:2333-2351`); the `config set` path has no equivalent.
+
+## Fix
+
+Carry the cleared paths alongside the partial, the way the conversation layer
+now does: have `build_partial_from_cfg_args` report the paths its arguments
+cleared, and have `set_in_conversations` pass them to `ApplyDelta::with_unsets`
+so a clear becomes a recorded delta.
+For the file target, a clear means removing the key from the file, which
+`ConfigFile`'s format-preserving edit already knows how to express.
+
+Failing either, the command should refuse `:=null` with an error naming the
+working alternative, rather than reporting a change it did not make.
+
+## Verifying
+
+A test asserting that `jp config set --id <id> --cfg assistant.name:=null`
+leaves the conversation resolving `assistant.name` to `None` on the next
+invocation, mirroring
+`resolve_config_keeps_a_cleared_conversation_field_across_invocations` in
+`crates/jp_cli/src/cmd/query_tests.rs`.
+
+[RFD 070]: https://jp.computer/rfd/070