#2451 ### More data for #1431: wrong parameter syntax inside an otherwise valid call (Coder IQ1_M on an Arc Pro B60)

Descripción

**Hardware note:** this is an **Intel Arc Pro B60** (`bmg-g21`, SYCL backend, built with `AOT=bmg-g21`). The startup banner says the SYCL backend was tested on an Arc Pro B70 and an Arc A750, so the B60 counts as untested. I have no B70 or CUDA card to check whether the rate is backend-specific, so treat that as an open question.

**Setup**
- Strata v0.1.44.1 (`296b59d`), SYCL backend, 1× Intel Arc Pro B60 (24 GB), Debian Linux 13 , Docker 29.8.1 (`ONEAPI_DEVICE_SELECTOR=level_zero:0`, `STRATA_EXPERT_SPLIT=1`)
- Model: Qwen3.8-Flash-Next **Coder IQ1_M** (`--kv int8`, `--max-context 131072`, 1 slot)
- Run config: `"tool_call_recovery": true`, `"fit_max_tokens": true`; reasoning effort left at the model default
- Client: Continue CLI (`cn`) through LiteLLM, OpenAI chat completions, streaming, **21 tools** (built-in `Bash`, `Read`, `List`, … plus MCP tools)
- Raw outputs captured with `STRATA_DEBUG=1`

<details>
<summary>Full configuration (compose environment, .env, setup command, engine arguments, run config)</summary>

`compose.yaml`, service `strata` (image built from the repo's `Dockerfile.b60`), environment:

~~~yaml
environment:
  STRATA_DEBUG: "1"
  AOT: bmg-g21
  REPO: ${STRATA_ROOT}/Strata
  BUILD_DIR: ${STRATA_ROOT}/Strata/build-sycl-aot
  JOBS: "28"
  STRATA_EXPERT_SPLIT: "1"

  ONEAPI_DEVICE_SELECTOR: level_zero:0
  SYCL_CACHE_PERSISTENT: "0"
  ZES_ENABLE_SYSMAN: "1"

  STRATA_SYCL_ROOT: ${STRATA_ROOT}
  STRATA_SYCL_IMAGE: strata-sycl-b60

  STRATA_VERIFY_DEVICE_PLAN: "1"
  STRATA_VERIFY_NO_HOST: "1"
  STRATA_MIRROR_MIB: "36864"
~~~

`.env` next to `compose.yaml` (`STRATA_ROOT` and `STRATA_API_KEY` omitted; the commented lines are the other quants used on the same setup):

~~~bash
#STRATA_MODEL=IQ3_S
#STRATA_MODEL=UD-IQ4_XS
STRATA_MODEL=IQ1_M
#STRATA_FAMILY=qwen
#STRATA_FAMILY=unsloth
STRATA_FAMILY=coder
STRATA_CONTEXT=131072
~~~

Container command (after an incremental SYCL build when the checked-out commit changed):

~~~bash
exec ./setup.sh \
  --backend sycl \
  --family ${STRATA_FAMILY} \
  --model ${STRATA_MODEL} \
  --gguf-dir "${STRATA_ROOT}/models/${STRATA_MODEL}" \
  --models-dir "${STRATA_ROOT}/models" \
  --data-dir "${STRATA_ROOT}/data" \
  --context ${STRATA_CONTEXT} \
  --kv int8 \
  --vision no \
  --host 0.0.0.0 \
  --port 8080 \
  --api-key "${STRATA_API_KEY}" \
  --yes
~~~

Engine arguments from `strata-coder-iq1_m.json` (paths omitted):

~~~text
--pack <path> --native <path> --ple-gguf <path> --expert-profile <path> --expert-cache auto --spec 4
--spec-min-p 0.5 --mtp <path> --max-context 131072 --kv int8 --kv-resident 32768 --stream-experts
--vram-reserve-mib 2048 --prefill 4096
~~~

Other run-config keys: `"backend": "sycl"`, `"tool_call_recovery": true`, `"reasoning_close_retry": true`, `"fit_max_tokens": true`.

</details>

**What happens**

The model opens the call correctly (`<tool_call>` + `<function=NAME>`), but writes the parameter tag in a different syntax. `parse_tool_call` only reads `<parameter=NAME>`, so the call reaches the client with **empty arguments** (`{}`), even though the full value is in the output. `tool_call_recovery` does not cover these forms.

It starts after roughly 15–25k prompt tokens and comes in streaks (2–3 broken calls in a row). It hits the `Bash` tool far more often than MCP tools with longer argument lists. Sampling made no difference: greedy and temperature 0.7 / top_p 0.8 / top_k 20 gave the same rate. No VRAM warnings in the log; `reasoning_close_retry` never fired.

Measured:
- 2026-10-13 (v0.1.43.1): 17 of 61 `Bash` calls broken in one 64-turn session
- 2026-10-14 (v0.1.44.1): 35 of 45 `Bash` calls broken in the first 30 min after a restart

**Tool schemas**
- `Bash` (Continue built-in): required string `command`, optional `timeout`
- `retry_code` (MCP): required strings `attempt_id` and `feedback`

**Raw outputs (exact, from the server log)**

1. Name as an XML-style attribute, quoted (most common on 14.10):

~~~text
<tool_call>
<function=Bash>
<parameter name="command">grep -rn "correction_fit\|correction_generate\|job_type\|correction" lotto_graph/services/lstm/correction/runner.py lotto_graph/api/routes/jobs.py 2>/dev/null | grep -v __pycache__ | sed -n '1,40p'
</parameter>
</function>
</tool_call><|im_end|>
~~~

2. Name as an attribute, unquoted:

~~~text
<tool_call>
<function=Bash>
<parameter name=command>
ls lotto_graph/worker.py 2>/dev/null; grep -rln "def.*job\|job_type\|correction" lotto_graph/worker.py 2>/dev/null
</parameter>
</function>
</tool_call><|im_end|>
~~~

3. All arguments as JSON in a nameless `<parameter>` (feedback shortened here):

~~~text
<tool_call>
<function=retry_code>
<parameter>
{"attempt_id": "bf3b0e1cb16b", "feedback": "Checked against the real repository file: `get_model` DOES exist on CorrectionRepository, so leave that call as it is. …"}
</parameter>
</function>
</tool_call>
~~~

4. Not recoverable, no value at all (observed bodies of `<function=Bash>`):

~~~text
<parameter name> command </parameter>
<parameter name> Bash </parameter>
<parameter> </parameter>
(empty body)
<｜end｜>
~~~

5. Also seen, rarer:
- `<arg_value>{"command": "grep -rn …"}` inside `<function=Bash>`
- `<function=Bash>` with `<parameter=dirpath>` (a parameter of the `List` tool)
- `<parameter=previous_thinking>`, `<parameter=parameter>`

Breakdown: on 13.10, 6 of the 17 broken calls carried the full value in a wrong syntax (forms 1–3) and 11 had none (form 4). On 14.10, 19 of 35 were forms 1–2, 3 were the `<arg_value>` JSON form and 13 had no value.

**Local workaround for forms 1–3 (patch below)**

A small patch on v0.1.44.1 (`serve/frontend.py`), active only with `"tool_call_recovery": true` and declared tools:
- inside `<function=…>…</function>` it rewrites `<parameter name="X">`, `<parameter name='X'>` and `<parameter name=X>` to `<parameter=X>`;
- it expands `<parameter>{json}</parameter>` into one `<parameter=key>` per key (non-string values as JSON);
- a new `ParamForms` class does this before `OutputParser` sees the text, holding a tag split across stream deltas until it is complete;
- text outside a call (reasoning, answer) is untouched.

It adds `serve/test_param_forms.py`: 9 tests built from the samples above, streamed in 1/3/7-character pieces and whole, inside and after the thinking, plus checks that the template form is unchanged, that the patch is off without `tool_call_recovery`, and that text outside a call is untouched. The existing parser tests (`test_tool_name_space`, `test_parser_track`, `test_reasoning_rescue`, `test_reasoning_tools`, `test_responses`) give the same results with and without it.

It does nothing for form 4, where the value is never generated; that probably needs the grammar-constrained emission proposed earlier in this issue. Happy to open a PR if this approach fits.

<details>
<summary>Patch against v0.1.44.1 (<code>git apply</code>)</summary>

~~~diff
diff --git a/serve/frontend.py b/serve/frontend.py
index c36a44d..909f364 100644
--- a/serve/frontend.py
+++ b/serve/frontend.py
@@ -870,6 +870,100 @@ def parse_tool_call(body: str, schema: dict | None = None) -> ToolCall:
 RCALL_MAX = 32768        # the most of a `<tool_call>` inside the reasoning that is held while waiting for its end (#804)
 
 
+class ParamForms:
+    """LOCAL PATCH (not upstream; see NOTATKI-ZMIANY.md next to the Strata checkout, 2026-10-14): rewrite parameter
+    tags the model writes in forms next to the template's into `<parameter=NAME>`, before OutputParser sees the
+    text.  Inside a `<function=...>` ... `</function>` only, and only with "tool_call_recovery" on:
+
+        <parameter name="NAME">  <parameter name='NAME'>  <parameter name=NAME>   -> <parameter=NAME>
+        <parameter>{"a": 1, "b": "x"}</parameter>                                 -> one <parameter=K> per key
+
+    Seen live (Qwen3.8-Flash-Next Coder IQ1_M, a coding agent with 21 tools): these calls carried the whole command
+    but came out with empty arguments, because parse_tool_call only reads `<parameter=NAME>`.  A tag split across
+    deltas is held back until it is complete, like the parser's own tags."""
+
+    NAMED = re.compile(r"""<parameter\s+name\s*=\s*(?:"([^"<>]*)"|'([^'<>]*)'|([^\s"'<>]+))\s*>""")
+    BARE = "<parameter>"
+    BARE_MAX = 65536             # the most of a nameless parameter held while waiting for its </parameter>
+
+    def __init__(self):
+        self.buf = ""
+        self.inside = False      # between a <function=...> and its </function>
+        self.rewritten = 0
+
+    def push(self, delta: str) -> str:
+        self.buf += delta
+        return self._drain(final=False)
+
+    def flush(self) -> str:
+        return self._drain(final=True)
+
+    @staticmethod
+    def _value(v) -> str:
+        return v if isinstance(v, str) else json.dumps(v, ensure_ascii=False)
+
+    def _drain(self, final: bool) -> str:
+        out = []
+        while self.buf:
+            if not self.inside:
+                i = self.buf.find(FUNC_START)
+                if i < 0:
+                    keep = 0
+                    if not final:        # the end may be the start of a `<function=`
+                        keep = next((n for n in range(min(len(FUNC_START) - 1, len(self.buf)), 0, -1)
+                                     if FUNC_START.startswith(self.buf[-n:])), 0)
+                    out.append(self.buf[:len(self.buf) - keep])
+                    self.buf = self.buf[len(self.buf) - keep:]
+                    break
+                out.append(self.buf[:i + len(FUNC_START)])
+                self.buf = self.buf[i + len(FUNC_START):]
+                self.inside = True
+                continue
+            i = self.buf.find("<")
+            if i < 0:
+                out.append(self.buf)
+                self.buf = ""
+                break
+            out.append(self.buf[:i])
+            self.buf = self.buf[i:]
+            if self.buf.startswith(FUNC_END):
+                out.append(FUNC_END)
+                self.buf = self.buf[len(FUNC_END):]
+                self.inside = False
+                continue
+            m = self.NAMED.match(self.buf)
+            if m:
+                out.append(PARAM_START + next(g for g in m.groups() if g is not None).strip() + ">")
+                self.buf = self.buf[m.end():]
+                self.rewritten += 1
+                continue
+            if self.buf.startswith(self.BARE):
+                close = self.buf.find(PARAM_END)
+                if close < 0 and not final and len(self.buf) < self.BARE_MAX:
+                    break                # wait for the whole nameless parameter
+                obj = None
+                if close >= 0:
+                    try:
+                        obj = json.loads(self.buf[len(self.BARE):close])
+                    except ValueError:
+                        obj = None
+                if isinstance(obj, dict) and obj:
+                    out.append("".join(f"<parameter={k}>\n{self._value(v)}\n</parameter>\n" for k, v in obj.items()))
+                    self.buf = self.buf[close + len(PARAM_END):].lstrip("\n")
+                    self.rewritten += 1
+                    continue
+                out.append(self.BARE)
+                self.buf = self.buf[len(self.BARE):]
+                continue
+            if not final and ">" not in self.buf and (
+                    any(t.startswith(self.buf) for t in (FUNC_END, self.BARE, "<parameter "))
+                    or self.buf.startswith("<parameter ")):
+                break                    # an unfinished tag that may still become one of the above
+            out.append("<")
+            self.buf = self.buf[1:]
+        return "".join(out)
+
+
 class OutputParser:
     """Incremental parser of the model's text. Feed deltas; get events. A tag split across deltas is held back
     until it is complete, so clients never see `<tool_` or `</thi`."""
@@ -898,6 +992,7 @@ class OutputParser:
         self.recover = recover