Bug: streamed tool calls assembled with empty name/callId when continuation deltas carry explicit id:""/name:null (dsh-llm-deepseek, rc.6 & rc.7)

[nyx-invoiss]

Versions: @deepseek-ai/dsh 0.1.0-rc.6 and 0.1.0-rc.7 (both reproduce) · headless profile · DSH_TOOLS_MODE=native · model deepseek-v4-flash served through an OpenAI-compatible gateway (DEEPSEEK_BASE_URL override).

Symptom

Every streamed tool call is assembled with an empty name and callId, so it fails tool-policy checks (tool "" is disabled …). The model retries a few steps, gives up, and the turn ends cleanly (finish=stop) with no output and nothing on stderr — from the harness's perspective nothing failed, which makes this very hard to notice in headless/CI use.

The same setup with deepseek-v4-pro works fine, which hid the bug for a while.

Root cause

dsh-llm-deepseek's translate() (lib/index.js ~L321 in the published package):

if (call.id !== void 0) block.callId = call.id;
if (call.function?.name !== void 0) block.name = call.function.name;

The guards only exclude undefined. Per the OpenAI streaming convention, tool_calls[].id and function.name are sent once in the first delta and continuation deltas omit them — but some backends/gateways serialize continuations with explicit id: "" and function: {name: null} instead of omitting the fields. Those explicit empty values pass the !== undefined guards and clobber the values captured from the first delta. closeBlock() then emits the block with name: block.name ?? "" → "", and BlockAssembler's "first close wins" rule locks the empty block in.

Observed on the wire (session JSONL): first tool-call-delta has id:"call_…", name:"read"; every continuation has id:"", name:null; the assembled tool/call event has name:"", callId:"".

Fix (verified)

Tighten both guards from "defined" to "non-empty":

if (call.id) block.callId = call.id;
if (call.function?.name) block.name = call.function.name;

With this two-line change, tool calls assemble correctly (name:"read", real callId) and the repro passes on both rc.6 and rc.7. An empty-string id/name carries no information, so ignoring falsy values can't lose anything a conformant stream would send.

Minimal repro

DSH_HOME=$(mktemp -d) DSH_TOOLS_MODE=native \
DEEPSEEK_BASE_URL=<openai-compatible gateway> DEEPSEEK_API_KEY=… \
dsh --profile headless "Use the read tool to read ./target.txt and reply with its first line."

against any backend that emits explicit id:""/name:null in tool-call continuation deltas (100% reproducible for us with deepseek-v4-flash behind vLLM-style gateways; deepseek-v4-pro omits the fields and is unaffected).

A related hardening suggestion: when a tool call does end up with an empty name, surfacing an explicit stream/protocol error would make this class of failure loud instead of a silent empty turn.

Happy to provide full session JSONL excerpts if useful. (Filed as a discussion since Issues are disabled on this repo.)

[denial123789]

补充一个面向操作者的判别方法。这里最容易误诊成“工具未注册”，但决定性证据其实在 identity 最后一次成功出现的位置：

• 如果完成的 tool/call 仍是 name:"read"，再去查 catalog / preset / policy。
• 如果首个 tool-call-delta 有 id:"call_…", name:"read"，后续同 index 出现 id:"", name:null，而完成事件变成 callId:"", name:""，问题在 policy 之前的 stream translation / close。
• rc.7 的 translate.ts 对两项都只排除 undefined，所以显式空值会覆盖首包身份；closeBlock() 再把空缺归一成空字符串。之后 BlockAssembler 把 block-end 当权威完成块，早期正确 delta 已不能修回这个 identity。
• 不建议通过允许空工具名、放宽 approval/sandbox/tool allowlist 来绕过。这会把一个协议身份错误变成未识别 effect 的执行风险。

最小证据包建议只保留：同一 call index 的有序 wire deltas、对应 Session raw chunks 与 completed tool/call、finish reason，以及同一只读 prompt 在“显式空值 route”和“后续字段省略 route”上的 A/B。注意区分 omitted / empty string / null，不要在整理日志时把三者合并。

回归测试需要至少两包：首包非空 identity，续包 id:"" / name:null 加 arguments fragment，最后断言 identity 保留且 arguments 完整。还应让“从未给出有效 name”的 call 在 policy 前显式报 protocol error，避免 headless/CI 里 clean stop + empty output。

完整的英文 capture、route isolation、source path 和 acceptance checklist：
https://sandbaseai.github.io/deepseek-harness-handbook/streamed-tool-call-identity.html

说明：这是按当前 rc.7 源码核对的独立社区 runbook，不代表修复已经进入官方发行版。

[hungnnvidia]

Proposed fix (fork PR; upstream rejects external PRs per CONTRIBUTING): hungnnvidia#1 — only assign tool-call id/name from non-empty strings so empty continuation deltas cannot clobber the first-delta identity.

[hungnnvidia]

Proposed fix (fork PR; upstream rejects external PRs per CONTRIBUTING): hungnnvidia#1 — only assign tool-call id/name from non-empty strings so empty continuation deltas do not clobber the first-delta identity.