diff --git a/Cargo.lock b/Cargo.lock
index e0bccea695..2490ba3939 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1845,6 +1845,7 @@ dependencies = [
  "sapling-renderdag",
  "scm-record",
  "serde",
+ "serde_json",
  "slab",
  "strsim",
  "tempfile",
diff --git a/cli/Cargo.toml b/cli/Cargo.toml
index 4ec287923f..57be178226 100644
--- a/cli/Cargo.toml
+++ b/cli/Cargo.toml
@@ -80,6 +80,7 @@ rpassword = { workspace = true }
 sapling-renderdag = { workspace = true }
 scm-record = { workspace = true }
 serde = { workspace = true }
+serde_json = { workspace = true }
 slab = { workspace = true }
 strsim = { workspace = true }
 tempfile = { workspace = true }
diff --git a/cli/src/commands/config/get.rs b/cli/src/commands/config/get.rs
index abeb4eebd2..70184cf78e 100644
--- a/cli/src/commands/config/get.rs
+++ b/cli/src/commands/config/get.rs
@@ -14,11 +14,13 @@
 
 use std::io::Write as _;
 
+use clap_complete::ArgValueCandidates;
 use tracing::instrument;
 
 use crate::cli_util::CommandHelper;
 use crate::command_error::config_error;
 use crate::command_error::CommandError;
+use crate::complete;
 use crate::config::ConfigNamePathBuf;
 use crate::ui::Ui;
 
@@ -34,7 +36,7 @@ use crate::ui::Ui;
 #[derive(clap::Args, Clone, Debug)]
 #[command(verbatim_doc_comment)]
 pub struct ConfigGetArgs {
-    #[arg(required = true)]
+    #[arg(required = true, add = ArgValueCandidates::new(complete::leaf_config_keys))]
     name: ConfigNamePathBuf,
 }
 
diff --git a/cli/src/commands/config/list.rs b/cli/src/commands/config/list.rs
index 8308171af9..e4501a40fb 100644
--- a/cli/src/commands/config/list.rs
+++ b/cli/src/commands/config/list.rs
@@ -12,11 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use clap_complete::ArgValueCandidates;
 use tracing::instrument;
 
 use super::ConfigLevelArgs;
 use crate::cli_util::CommandHelper;
 use crate::command_error::CommandError;
+use crate::complete;
 use crate::config::to_toml_value;
 use crate::config::AnnotatedValue;
 use crate::config::ConfigNamePathBuf;
@@ -31,6 +33,7 @@ use crate::ui::Ui;
 #[command(mut_group("config_level", |g| g.required(false)))]
 pub struct ConfigListArgs {
     /// An optional name of a specific config option to look up.
+    #[arg(add = ArgValueCandidates::new(complete::config_keys))]
     pub name: Option<ConfigNamePathBuf>,
     /// Whether to explicitly include built-in default values in the list.
     #[arg(long, conflicts_with = "config_level")]
diff --git a/cli/src/commands/config/set.rs b/cli/src/commands/config/set.rs
index e4a9106edc..ff4f816c5f 100644
--- a/cli/src/commands/config/set.rs
+++ b/cli/src/commands/config/set.rs
@@ -14,6 +14,7 @@
 
 use std::io;
 
+use clap_complete::ArgValueCandidates;
 use jj_lib::commit::Commit;
 use jj_lib::repo::Repo;
 use tracing::instrument;
@@ -24,6 +25,7 @@ use crate::cli_util::CommandHelper;
 use crate::cli_util::WorkspaceCommandHelper;
 use crate::command_error::user_error;
 use crate::command_error::CommandError;
+use crate::complete;
 use crate::config::parse_toml_value_or_bare_string;
 use crate::config::write_config_value_to_file;
 use crate::config::ConfigNamePathBuf;
@@ -32,7 +34,7 @@ use crate::ui::Ui;
 /// Update config file to set the given option to a given value.
 #[derive(clap::Args, Clone, Debug)]
 pub struct ConfigSetArgs {
-    #[arg(required = true)]
+    #[arg(required = true, add = ArgValueCandidates::new(complete::leaf_config_keys))]
     name: ConfigNamePathBuf,
     #[arg(required = true)]
     value: String,
diff --git a/cli/src/commands/config/unset.rs b/cli/src/commands/config/unset.rs
index 46a8446f39..1b8400c7af 100644
--- a/cli/src/commands/config/unset.rs
+++ b/cli/src/commands/config/unset.rs
@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use clap_complete::ArgValueCandidates;
 use tracing::instrument;
 
 use super::ConfigLevelArgs;
@@ -19,6 +20,7 @@ use crate::cli_util::get_new_config_file_path;
 use crate::cli_util::CommandHelper;
 use crate::command_error::user_error;
 use crate::command_error::CommandError;
+use crate::complete;
 use crate::config::remove_config_value_from_file;
 use crate::config::ConfigNamePathBuf;
 use crate::ui::Ui;
@@ -26,7 +28,7 @@ use crate::ui::Ui;
 /// Update config file to unset the given option.
 #[derive(clap::Args, Clone, Debug)]
 pub struct ConfigUnsetArgs {
-    #[arg(required = true)]
+    #[arg(required = true, add = ArgValueCandidates::new(complete::leaf_config_keys))]
     name: ConfigNamePathBuf,
     #[command(flatten)]
     level: ConfigLevelArgs,
diff --git a/cli/src/commands/util/config_schema.rs b/cli/src/commands/util/config_schema.rs
index 7923dc02f6..91e464a5e4 100644
--- a/cli/src/commands/util/config_schema.rs
+++ b/cli/src/commands/util/config_schema.rs
@@ -16,6 +16,7 @@ use std::io::Write as _;
 
 use crate::cli_util::CommandHelper;
 use crate::command_error::CommandError;
+use crate::config::CONFIG_SCHEMA;
 use crate::ui::Ui;
 
 /// Print the JSON schema for the jj TOML config format.
@@ -27,8 +28,6 @@ pub fn cmd_util_config_schema(
     _command: &CommandHelper,
     _args: &UtilConfigSchemaArgs,
 ) -> Result<(), CommandError> {
-    // TODO(#879): Consider generating entire schema dynamically vs. static file.
-    let buf = include_bytes!("../../config-schema.json");
-    ui.stdout().write_all(buf)?;
+    ui.stdout().write_all(CONFIG_SCHEMA.as_bytes())?;
     Ok(())
 }
diff --git a/cli/src/complete.rs b/cli/src/complete.rs
index d138dc4327..6418849afb 100644
--- a/cli/src/complete.rs
+++ b/cli/src/complete.rs
@@ -26,7 +26,9 @@ use crate::cli_util::GlobalArgs;
 use crate::command_error::user_error;
 use crate::command_error::CommandError;
 use crate::config::default_config;
+use crate::config::ConfigNamePathBuf;
 use crate::config::LayeredConfigs;
+use crate::config::CONFIG_SCHEMA;
 use crate::ui::Ui;
 
 const BOOKMARK_HELP_TEMPLATE: &str = r#"
@@ -292,6 +294,66 @@ pub fn workspaces() -> Vec<CompletionCandidate> {
     })
 }
 
+fn config_keys_rec(
+    prefix: ConfigNamePathBuf,
+    properties: &serde_json::Map<String, serde_json::Value>,
+    acc: &mut Vec<CompletionCandidate>,
+    only_leaves: bool,
+) {
+    for (key, value) in properties {
+        let mut prefix = prefix.clone();
+        prefix.push(key);
+
+        let value = value.as_object().unwrap();
+        match value.get("type").and_then(|v| v.as_str()) {
+            Some("object") => {
+                if !only_leaves {
+                    let help = value
+                        .get("description")
+                        .map(|desc| desc.as_str().unwrap().to_string().into());
+                    let escaped_key = prefix.to_string();
+                    acc.push(CompletionCandidate::new(escaped_key).help(help));
+                }
+                let Some(properties) = value.get("properties") else {
+                    continue;
+                };
+                let properties = properties.as_object().unwrap();
+                config_keys_rec(prefix, properties, acc, only_leaves);
+            }
+            _ => {
+                let help = value
+                    .get("description")
+                    .map(|desc| desc.as_str().unwrap().to_string().into());
+                let escaped_key = prefix.to_string();
+                acc.push(CompletionCandidate::new(escaped_key).help(help));
+            }
+        }
+    }
+}
+
+fn config_keys_impl(only_leaves: bool) -> Vec<CompletionCandidate> {
+    let schema: serde_json::Value = serde_json::from_str(CONFIG_SCHEMA).unwrap();
+    let schema = schema.as_object().unwrap();
+    let properties = schema["properties"].as_object().unwrap();
+
+    let mut candidates = Vec::new();
+    config_keys_rec(
+        ConfigNamePathBuf::root(),
+        properties,
+        &mut candidates,
+        only_leaves,
+    );
+    candidates
+}
+
+pub fn config_keys() -> Vec<CompletionCandidate> {
+    config_keys_impl(false)
+}
+
+pub fn leaf_config_keys() -> Vec<CompletionCandidate> {
+    config_keys_impl(true)
+}
+
 /// Shell out to jj during dynamic completion generation
 ///
 /// In case of errors, print them and early return an empty vector.
@@ -402,3 +464,14 @@ fn get_jj_command() -> Result<(std::process::Command, Config), CommandError> {
 
     Ok((cmd, config))
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_config_keys() {
+        // Just make sure the schema is parsed without failure.
+        let _ = config_keys();
+    }
+}
diff --git a/cli/src/config.rs b/cli/src/config.rs
index 9f424567be..71b5775ba6 100644
--- a/cli/src/config.rs
+++ b/cli/src/config.rs
@@ -35,6 +35,9 @@ use crate::command_error::user_error;
 use crate::command_error::user_error_with_message;
 use crate::command_error::CommandError;
 
+// TODO(#879): Consider generating entire schema dynamically vs. static file.
+pub const CONFIG_SCHEMA: &str = include_str!("config-schema.json");
+
 /// Parses a TOML value expression. Interprets the given value as string if it
 /// can't be parsed.
 pub fn parse_toml_value_or_bare_string(value_str: &str) -> toml_edit::Value {
diff --git a/cli/tests/test_completion.rs b/cli/tests/test_completion.rs
index 3bd1fff788..d7d1031c02 100644
--- a/cli/tests/test_completion.rs
+++ b/cli/tests/test_completion.rs
@@ -472,3 +472,25 @@ fn test_workspaces() {
     default	initial
     ");
 }
+
+#[test]
+fn test_config() {
+    let mut test_env = TestEnvironment::default();
+    test_env.add_env_var("COMPLETE", "fish");
+    let dir = test_env.env_root();
+
+    let stdout = test_env.jj_cmd_success(dir, &["--", "jj", "config", "get", "c"]);
+    insta::assert_snapshot!(stdout, @r"
+    core.fsmonitor	Whether to use an external filesystem monitor, useful for large repos
+    core.watchman.register_snapshot_trigger	Whether to use triggers to monitor for changes in the background.
+    ");
+
+    let stdout = test_env.jj_cmd_success(dir, &["--", "jj", "config", "list", "c"]);
+    insta::assert_snapshot!(stdout, @r"
+    colors	Mapping from jj formatter labels to colors
+    core
+    core.fsmonitor	Whether to use an external filesystem monitor, useful for large repos
+    core.watchman
+    core.watchman.register_snapshot_trigger	Whether to use triggers to monitor for changes in the background.
+    ");
+}