# Kimi Code 0.21.0

- Product: Kimi Code (https://whatsnew.fyi/product/kimi-code)
- Vendor: Moonshot AI
- Date: 2026-07-01
- Version: 0.21.0
- Original notes: https://github.com/MoonshotAI/kimi-code/releases/tag/%40moonshot-ai/kimi-code%400.21.0
- Permalink: https://whatsnew.fyi/product/kimi-code/releases/0.21.0
- Labels: Platforms: Desktop

What's New is an index, not a publisher: every entry below links to the vendor's own release notes, which are the authoritative source. Entries are labelled where they are hand-curated sample data, pre-releases, or drawn from a secondary source such as a developer blog.

Reuse: the summaries, labels and curation here are © What's New. Quote freely with attribution and a link back; wholesale republication of the corpus is not permitted — terms: https://whatsnew.fyi/terms. The vendors' own release notes remain their publishers'.

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- **added** — Plugins can now provide slash commands via a commands field in their manifest, registered as <plugin>:<command> and invoked with $ARGUMENTS expansion
- **changed** — Rework conversation compaction to keep only recent user prompts plus a single user-role summary and drop assistant and tool messages
- **fixed** — Repair tool_use/tool_result adjacency before sending to fix HTTP 400 errors when a tool call and its result became non-adjacent
- **fixed** — Merge consecutive user turns for strict providers (Gemini/Vertex) to fix HTTP 400 errors after compaction or when a turn is steered in right after a tool result
- **changed** — Micro-compaction now defaults off
- **changed** — Refactor the thinking effort system
- **added** — Add a server-side key-value store API for persisting web UI preferences to the user's data directory
- **added** — Add a double-Esc shortcut to open the undo selector
- **fixed** — Fix @ file mentions not opening when typed inside a slash command argument
- **fixed** — Force-exit headless runs so a stray ref'd handle left over from the run can't keep a completed run alive until an external timeout
- **added** — Show file path completions when typing / in shell mode (!)
- **fixed** — Fix adding a workspace by path in the web UI failing silently when the daemon rejects the path; it now shows an error instead
- **fixed** — Fix duplicate workspaces showing in the web sidebar when the same folder is registered more than once
- **fixed** — Stop a malformed message history from permanently bricking a session on strict providers; the request is repaired before sending and resent once with a wire-compliant rebuild if the provider still rejects it
- **changed** — Split LLM streaming timing in the session log into client vs. API-server portions to help attribute slow turns without parsing the wire log
- **added** — Add Mermaid diagram rendering to the web chat for fenced mermaid blocks in assistant responses
- **changed** — KaTeX math and Mermaid diagram parsing now run in Web Workers to keep the UI responsive during live streaming
- **changed** — Always show the usage-data opt-out toggle in the web settings with a clearer label and description
- **fixed** — Fix the web workspace rename not persisting after a page refresh

###### Minor Changes

- [#1204](https://github.com/MoonshotAI/kimi-code/pull/1204) [`5cb80ce`](https://github.com/MoonshotAI/kimi-code/commit/5cb80ce879406d239048c32d61202778cb860e58) - Plugins can now provide slash commands via a `commands` field in their manifest, registered as `<plugin>:<command>` and invoked with `$ARGUMENTS` expansion.

- [#1214](https://github.com/MoonshotAI/kimi-code/pull/1214) [`86e0c92`](https://github.com/MoonshotAI/kimi-code/commit/86e0c9201ed58c7c1ce5543b1dfb47a4cf5117f6) - Rework conversation compaction:

  - Keep only recent user prompts plus a single user-role summary; drop assistant and tool messages.
  - Repair tool_use/tool_result adjacency before sending, fixing a strict-provider HTTP 400 when a tool call and its result became non-adjacent.
  - Merge consecutive user turns for strict providers (Gemini/Vertex), fixing an HTTP 400 ("roles must alternate") after compaction or when a turn is steered in right after a tool result.
  - Micro-compaction now defaults off.

- [#1132](https://github.com/MoonshotAI/kimi-code/pull/1132) [`108299b`](https://github.com/MoonshotAI/kimi-code/commit/108299be3cdffc31a23f64efd3ff5ba50976b412) - Refactor the thinking effort system

###### Patch Changes

- [#1231](https://github.com/MoonshotAI/kimi-code/pull/1231) [`ceb27f5`](https://github.com/MoonshotAI/kimi-code/commit/ceb27f5e449e177493f320d90e292487a8fc3410) - Add a server-side key-value store API for persisting web UI preferences to the user's data directory.

- [#1220](https://github.com/MoonshotAI/kimi-code/pull/1220) [`ec51324`](https://github.com/MoonshotAI/kimi-code/commit/ec51324230484f2ebaad1ab0aebf2e38f531d914) - Add a double-Esc shortcut to open the undo selector. Press Esc twice while idle to undo.

- [#1223](https://github.com/MoonshotAI/kimi-code/pull/1223) [`80e6888`](https://github.com/MoonshotAI/kimi-code/commit/80e6888e34e4362247c0eac5b77340df014ba286) - Fix @ file mentions not opening when typed inside a slash command argument.

- [#1233](https://github.com/MoonshotAI/kimi-code/pull/1233) [`020992c`](https://github.com/MoonshotAI/kimi-code/commit/020992c286f0f6bff6a038a7c7bd7e9db639e3c9) - Force-exit headless runs (`kimi -p`) so a stray ref'd handle left over from the run can't keep a completed run alive until an external timeout, and bound prompt cleanup so a wedged shutdown step can't hang shutdown.

- [#1225](https://github.com/MoonshotAI/kimi-code/pull/1225) [`659062d`](https://github.com/MoonshotAI/kimi-code/commit/659062d11cc272fe631fc6d4faf64d0e0b1a0142) - Show file path completions when typing `/` in shell mode (`!`).

- [#1236](https://github.com/MoonshotAI/kimi-code/pull/1236) [`bfe8e6a`](https://github.com/MoonshotAI/kimi-code/commit/bfe8e6ace3cda76b1991bf29c25b9444611d5512) - Fix adding a workspace by path in the web UI failing silently when the daemon rejects the path; it now shows an error instead of a broken workspace.

- [#1221](https://github.com/MoonshotAI/kimi-code/pull/1221) [`a3f9cec`](https://github.com/MoonshotAI/kimi-code/commit/a3f9cec8a975f11e37e992e42f954789ed394207) - Fix duplicate workspaces showing in the web sidebar when the same folder is registered more than once.

- [#1241](https://github.com/MoonshotAI/kimi-code/pull/1241) [`8ac337a`](https://github.com/MoonshotAI/kimi-code/commit/8ac337a2b2ac800aa79a373459308abb6c9e63bb) - Stop a malformed message history from permanently bricking a session on strict providers (Anthropic). The request is repaired before sending — orphaned tool calls are closed and empty/whitespace-only text blocks dropped — and if the provider still rejects its structure, it is resent once with a wire-compliant rebuild.

- [#1228](https://github.com/MoonshotAI/kimi-code/pull/1228) [`42e37eb`](https://github.com/MoonshotAI/kimi-code/commit/42e37eb898b722829d2ec83e909525ff18e336a5) - Split LLM streaming timing in the session log and `KIMI_CODE_DEBUG=1` output into client vs. API-server portions, so slow turns can be attributed without parsi

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