diff --git a/crates/tinyagents-harness/src/tool_calling/parse.rs b/crates/tinyagents-harness/src/tool_calling/parse.rs
index 31562fae..356a9994 100644
--- a/crates/tinyagents-harness/src/tool_calling/parse.rs
+++ b/crates/tinyagents-harness/src/tool_calling/parse.rs
@@ -206,23 +206,194 @@ static TOOL_CALL_TAG_RE: LazyLock<Regex> =
 /// `Borrowed` no-op unless a *piped* tag is actually present, so well-formed
 /// output — which the base parser already handles — and P-Format pipe args are
 /// untouched.
+static DSML_CALLS_BLOCK_RE: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(
+        r"(?is)<[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*calls?\s*>(.*?)(?:</[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*calls?\s*>|<[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*/calls?\s*>|</tool_call>|$)",
+    )
+    .unwrap()
+});
+
+static DSML_INVOKE_OPEN_RE: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(
+        r#"(?is)<(?:[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*)?invoke\s+name\s*=\s*"([^"]+)"[^>]*>"#,
+    )
+    .unwrap()
+});
+
+static DSML_INVOKE_CLOSE_RE: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(r"(?is)</(?:[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*)?invoke\s*>|</tool_call>").unwrap()
+});
+
+static DSML_PARAMETER_OPEN_RE: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(
+        r#"(?is)<(?:[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*)?parameter(?:\s+name\s*=\s*"([^"]*)")?[^>]*>"#,
+    )
+    .unwrap()
+});
+
+static DSML_PARAMETER_CLOSE_RE: LazyLock<Regex> = LazyLock::new(|| {
+    Regex::new(r"(?is)</(?:[|｜]{1,2}\s*DSML\s*[|｜]{1,2}\s*)?parameter\s*>").unwrap()
+});
+
+/// Parse arguments from a DSML `<invoke>` block body.
+///
+/// Handles:
+/// 1. `<parameter name="...">value</parameter>` tags (single `arguments` envelope or multiple named params).
+/// 2. Direct JSON object bodies (when the model omits `<parameter>` tags or emits only a closing `</parameter>` tag).
+/// 3. Empty bodies (`{}`).
+fn parse_dsml_invoke_arguments(body: &str) -> serde_json::Value {
+    let param_matches: Vec<_> = DSML_PARAMETER_OPEN_RE.captures_iter(body).collect();
+    let mut named_params = Vec::new();
+    for (i, cap) in param_matches.iter().enumerate() {
+        let name = cap.get(1).map(|m| m.as_str().trim()).unwrap_or("");
+        let start = cap.get(0).unwrap().end();
+        let end = if i + 1 < param_matches.len() {
+            param_matches[i + 1].get(0).unwrap().start()
+        } else {
+            body.len()
+        };
+        let mut raw_val = &body[start..end];
+        if let Some(close_m) = DSML_PARAMETER_CLOSE_RE.find(raw_val) {
+            raw_val = &raw_val[..close_m.start()];
+        }
+        let val = raw_val.trim();
+        if !name.is_empty() {
+            named_params.push((name, val));
+        }
+    }
+
+    if !named_params.is_empty() {
+        if named_params.len() == 1 && TOOL_ARG_KEYS.contains(&named_params[0].0) {
+            let val_str = named_params[0].1;
+            if let Some((json_val, _)) = extract_first_json_value_with_end(val_str)
+                && json_val.is_object()
+            {
+                return json_val;
+            }
+            if let Ok(json_val) = serde_json::from_str::<serde_json::Value>(val_str) {
+                if json_val.is_object() {
+                    return json_val;
+                }
+                return serde_json::json!({ named_params[0].0: json_val });
+            }
+            return serde_json::json!({ named_params[0].0: val_str });
+        }
+
+        let mut map = serde_json::Map::new();
+        for (pname, pval_str) in named_params {
+            map.insert(pname.to_string(), parameter_scalar_value(pval_str));
+        }
+        return serde_json::Value::Object(map);
+    }
+
+    // Bare JSON object directly inside invoke body (with or without unclosed parameter tags)
+    if let Some((json_val, _)) = extract_first_json_value_with_end(body)
+        && json_val.is_object()
+    {
+        return json_val;
+    }
+
+    let trimmed = body.trim();
+    if trimmed.is_empty() {
+        return serde_json::Value::Object(serde_json::Map::new());
+    }
+
+    serde_json::json!({ "input": trimmed })
+}
+
+/// Normalize DeepSeek DSML tool calls (`<｜｜DSML｜｜ calls><｜｜DSML｜｜ invoke name="...">...</｜｜DSML｜｜ calls>`)
+/// into canonical `<tool_call>` tags with JSON payloads.
+///
+/// DeepSeek models (such as DeepSeek-V3, DeepSeek-V4, DeepSeek-Flash) emit DSML syntax when asked
+/// to invoke tools in text/P-Format mode. Without this normalization, OpenHuman treats DSML tags
+/// as narrative text and fails to execute the tool calls.
+fn normalize_dsml_tool_calls(s: &str) -> Cow<'_, str> {
+    if !s.contains("DSML") && !s.contains("dsml") {
+        return Cow::Borrowed(s);
+    }
+
+    if !DSML_CALLS_BLOCK_RE.is_match(s) {
+        return Cow::Borrowed(s);
+    }
+
+    let mut out = String::with_capacity(s.len());
+    let mut cursor = 0;
+
+    for mat in DSML_CALLS_BLOCK_RE.find_iter(s) {
+        let block_start = mat.start();
+        let block_end = mat.end();
+        out.push_str(&s[cursor..block_start]);
+
+        let block_match = DSML_CALLS_BLOCK_RE.captures(&s[block_start..block_end]);
+        let inner = block_match
+            .and_then(|c| c.get(1))
+            .map(|m| m.as_str())
+            .unwrap_or("");
+
+        let invoke_matches: Vec<_> = DSML_INVOKE_OPEN_RE.captures_iter(inner).collect();
+        let mut recovered_any = false;
+        for (i, inv_cap) in invoke_matches.iter().enumerate() {
+            let name = inv_cap.get(1).map(|m| m.as_str().trim()).unwrap_or("");
+            if name.is_empty() {
+                continue;
+            }
+            let body_start = inv_cap.get(0).unwrap().end();
+            let body_end = if i + 1 < invoke_matches.len() {
+                invoke_matches[i + 1].get(0).unwrap().start()
+            } else {
+                inner.len()
+            };
+            let mut raw_body = &inner[body_start..body_end];
+            if let Some(close_m) = DSML_INVOKE_CLOSE_RE.find(raw_body) {
+                raw_body = &raw_body[..close_m.start()];
+            }
+
+            let arguments = parse_dsml_invoke_arguments(raw_body);
+
+            let payload = serde_json::json!({
+                "name": name,
+                "arguments": arguments,
+            });
+            out.push_str("<tool_call>\n");
+            out.push_str(&payload.to_string());
+            out.push_str("\n</tool_call>");
+            recovered_any = true;
+        }
+
+        if !recovered_any {
+            out.push_str(&s[block_start..block_end]);
+        } else {
+            tinyagents_tracing::debug!(
+                "[agent_parse] normalized DeepSeek DSML tool calls into canonical <tool_call> tags"
+            );
+        }
+
+        cursor = block_end;
+    }
+
+    out.push_str(&s[cursor..]);
+    Cow::Owned(out)
+}
+
 fn normalize_garbled_tool_call_tags(s: &str) -> Cow<'_, str> {
+    let s = normalize_dsml_tool_calls(s);
+    let s_ref = s.as_ref();
     // Garbling always leaks a `|` into a tag; no `|` anywhere → nothing to do.
-    if !s.contains('|') {
-        return Cow::Borrowed(s);
+    if !s_ref.contains('|') {
+        return s;
     }
     let tags: Vec<(usize, usize)> = TOOL_CALL_TAG_RE
-        .find_iter(s)
+        .find_iter(s_ref)
         .map(|m| (m.start(), m.end()))
         .collect();
     // Need at least one open/close pair, and at least one tag must actually be
     // garbled (contain a pipe) — otherwise the base parser handles it verbatim,
     // and P-Format `name[a|b]` args (pipes in the BODY, not the tags) are left
     // alone.
-    if tags.len() < 2 || !tags.iter().any(|&(a, b)| s[a..b].contains('|')) {
-        return Cow::Borrowed(s);
+    if tags.len() < 2 || !tags.iter().any(|&(a, b)| s_ref[a..b].contains('|')) {
+        return s;
     }
-    let mut out = String::with_capacity(s.len());
+    let mut out = String::with_capacity(s_ref.len());
     let mut cursor = 0usize;
     // `as_chunks::<2>()` rather than `chunks_exact(2)`: the chunk size is a
     // constant, so this hands back fixed-size arrays and the two destructurings
@@ -231,13 +402,13 @@ fn normalize_garbled_tool_call_tags(s: &str) -> Cow<'_, str> {
     for &[open, close] in tags.as_chunks::<2>().0 {
         let (open_start, open_end) = open;
         let (close_start, close_end) = close;
-        out.push_str(&s[cursor..open_start]); // text before the open tag, verbatim
+        out.push_str(&s_ref[cursor..open_start]); // text before the open tag, verbatim
         out.push_str("<tool_call>");
         // Strip the `call:` prefix, then try to recover a Kimi-family
         // `NAME{…}` argument-sentinel body into canonical JSON (#5119). When
         // the body is already canonical JSON / P-Format the recovery is a no-op
         // and the stripped body flows through unchanged.
-        let stripped = strip_call_prefix(&s[open_end..close_start]);
+        let stripped = strip_call_prefix(&s_ref[open_end..close_start]);
         match recover_sentinel_tool_call_body(stripped) {
             Some(recovered) => {
                 // Recovered a Kimi-family `NAME{…}` sentinel body into canonical
@@ -269,7 +440,7 @@ fn normalize_garbled_tool_call_tags(s: &str) -> Cow<'_, str> {
         cursor = close_end;
     }
     // Trailing text, plus any final unpaired tag, verbatim.
-    out.push_str(&s[cursor..]);
+    out.push_str(&s_ref[cursor..]);
     Cow::Owned(out)
 }
 
diff --git a/crates/tinyagents-harness/src/tool_calling/parse_test.rs b/crates/tinyagents-harness/src/tool_calling/parse_test.rs
index a2072971..805cbe8f 100644
--- a/crates/tinyagents-harness/src/tool_calling/parse_test.rs
+++ b/crates/tinyagents-harness/src/tool_calling/parse_test.rs
@@ -520,3 +520,138 @@ fn a_tagged_body_still_honours_argument_key_aliases() {
         .expect("the aliased tagged call must survive");
     assert_eq!(shell.arguments["command"], "ls");
 }
+
+// ── DeepSeek DSML tool-call format recovery ──────────────────────────────────
+
+#[test]
+fn dsml_parameter_with_arguments_envelope_parses() {
+    let response = concat!(
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"GMAIL_FETCH_EMAILS\">\n",
+        "<｜｜DSML｜｜ parameter name=\"arguments\" string=\"false\">{\"max_results\": 10, \"query\": \"in:inbox\", \"user_id\": \"me\"}</｜｜DSML｜｜ parameter>\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "</｜｜DSML｜｜ calls>"
+    );
+    let (narrative, calls) = parse_tool_calls(response);
+    assert!(narrative.is_empty());
+    assert_eq!(calls.len(), 1);
+    assert_eq!(calls[0].name, "GMAIL_FETCH_EMAILS");
+    assert_eq!(calls[0].arguments["max_results"], 10);
+    assert_eq!(calls[0].arguments["query"], "in:inbox");
+    assert_eq!(calls[0].arguments["user_id"], "me");
+}
+
+#[test]
+fn dsml_invoke_with_direct_json_body_parses() {
+    let response = concat!(
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"composio_list_tools\">\n",
+        "{\"toolkits\":[\"gmail\"]}\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "</｜｜DSML｜｜ calls>"
+    );
+    let (_narrative, calls) = parse_tool_calls(response);
+    assert_eq!(calls.len(), 1);
+    assert_eq!(calls[0].name, "composio_list_tools");
+    assert_eq!(calls[0].arguments["toolkits"], serde_json::json!(["gmail"]));
+}
+
+#[test]
+fn dsml_invoke_with_orphan_closing_parameter_tag_parses() {
+    let response = concat!(
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"GMAIL_FETCH_EMAILS\">\n",
+        "{\"label_ids\": [\"INBOX\"], \"ids_only\": true, \"max_results\": 500, \"include_payload\": false, \"verbose\": false}\n",
+        "</｜｜DSML｜｜ parameter>\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "</｜｜DSML｜｜ calls>"
+    );
+    let (_narrative, calls) = parse_tool_calls(response);
+    assert_eq!(calls.len(), 1);
+    assert_eq!(calls[0].name, "GMAIL_FETCH_EMAILS");
+    assert_eq!(
+        calls[0].arguments["label_ids"],
+        serde_json::json!(["INBOX"])
+    );
+    assert_eq!(calls[0].arguments["max_results"], 500);
+}
+
+#[test]
+fn dsml_multiple_invokes_with_empty_args_and_narrative_text_parses() {
+    let response = concat!(
+        "I'll verify Gmail access by fetching the profile and listing recent inbox messages.\n\n",
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"GMAIL_GET_PROFILE\">\n\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "<｜｜DSML｜｜ invoke name=\"GMAIL_FETCH_EMAILS\">\n",
+        "{\"label_ids\": [\"INBOX\"], \"max_results\": 5, \"verbose\": false}\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "</｜｜DSML｜｜ calls>"
+    );
+    let (narrative, calls) = parse_tool_calls(response);
+    assert_eq!(
+        narrative,
+        "I'll verify Gmail access by fetching the profile and listing recent inbox messages."
+    );
+    assert_eq!(calls.len(), 2);
+    assert_eq!(calls[0].name, "GMAIL_GET_PROFILE");
+    assert_eq!(calls[0].arguments, serde_json::json!({}));
+    assert_eq!(calls[1].name, "GMAIL_FETCH_EMAILS");
+    assert_eq!(
+        calls[1].arguments["label_ids"],
+        serde_json::json!(["INBOX"])
+    );
+    assert_eq!(calls[1].arguments["max_results"], 5);
+}
+
+#[test]
+fn dsml_parameter_with_named_arguments_parses() {
+    let response = concat!(
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"composio_list_tools\">\n",
+        "<｜｜DSML｜｜ parameter name=\"toolkits\" string=\"true\">[\"twitter\"]</｜｜DSML｜｜ parameter>\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "</｜｜DSML｜｜ calls>"
+    );
+    let (_narrative, calls) = parse_tool_calls(response);
+    assert_eq!(calls.len(), 1);
+    assert_eq!(calls[0].name, "composio_list_tools");
+    assert_eq!(
+        calls[0].arguments["toolkits"],
+        serde_json::json!(["twitter"])
+    );
+}
+
+#[test]
+fn dsml_mixed_tool_call_closing_tag_parses() {
+    let response = concat!(
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"GMAIL_FETCH_EMAILS\">\n",
+        "{\"label_ids\": [\"INBOX\"], \"max_results\": 2}\n",
+        "</tool_call>"
+    );
+    let (_narrative, calls) = parse_tool_calls(response);
+    assert_eq!(calls.len(), 1);
+    assert_eq!(calls[0].name, "GMAIL_FETCH_EMAILS");
+    assert_eq!(
+        calls[0].arguments["label_ids"],
+        serde_json::json!(["INBOX"])
+    );
+    assert_eq!(calls[0].arguments["max_results"], 2);
+}
+
+#[test]
+fn dsml_with_pformat_registry_recovers_cleanly() {
+    let reg = PFormatRegistry::new();
+    let response = concat!(
+        "<｜｜DSML｜｜ calls>\n",
+        "<｜｜DSML｜｜ invoke name=\"GMAIL_FETCH_EMAILS\">\n",
+        "<｜｜DSML｜｜ parameter name=\"arguments\">{\"label_ids\": [\"INBOX\"], \"max_results\": 3}</｜｜DSML｜｜ parameter>\n",
+        "</｜｜DSML｜｜ invoke>\n",
+        "</｜｜DSML｜｜ calls>"
+    );
+    let (_narrative, calls) = parse_tool_calls_with_pformat(response, &reg);
+    assert_eq!(calls.len(), 1);
+    assert_eq!(calls[0].name, "GMAIL_FETCH_EMAILS");
+    assert_eq!(calls[0].arguments["max_results"], 3);
+}