claude-code - 💡(How to fix) Fix [BUG] Agent-team teammate pane crashes with "<Box> can't be nested inside <Text>" when ※ recap renders inline markdown code spans [8 comments, 8 participants]

Title: [BUG] Agent-team teammate pane crashes with "<Box> can't be nested inside <Text>" when ※ recap renders inline markdown code spans

Summary

In Claude Code v2.1.117 agent-teams mode, if a teammate's reply to team-lead contains inline markdown code spans (backtick-delimited text like `uv run python`), the teammate's own pane crashes when Claude Code renders the ※ recap: compact-summary line. The Ink reconciler throws Error: <Box> can't be nested inside <Text> component from createInstance at cli.js:495:249. The crashed pane subsequently causes the whole team directory (~/.claude/teams/{name}/) to be torn down, cascading to all other teammates.

This is distinct from #49865 (different error, different line, different trigger — and #49865 is fixed as of v2.1.114).

Environment

• Claude Code: v2.1.117 (confirmed), v2.1.116 (strongly suspected based on retrospective matching against prior session stalls, not re-tested)
• Platform: macOS (Darwin 24.5.0)
• Terminal: iTerm2 inside tmux (tmux -CC control mode)
• Model: Sonnet 4.6 / Opus 4.7 (both observed)
• Feature flag: CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1

Error (verbatim, from crashed pane)

Error: <Box> can't be nested inside <Text> component
    at createInstance  /$bunfs/root/src/entrypoints/cli.js:495:249
    at BU              cli.js:477:57938
    at gTH / XWH / bgH / Ir / MWH / T_ / hH / eH
       (React Fiber reconciler + Ink host config work loop)

The throw site in the bundled source:

createInstance(H, _, q, K, O) {
  if (K.isInsideText && H === "ink-box")
    throw Error("<Box> can't be nested inside <Text> component");

Combined with the host-context tracker a few lines earlier:

getChildHostContext(H, _) {
  let q = H.isInsideText,
      K = _ === "ink-text" || _ === "ink-virtual-text" || _ === "ink-link";
  if (q === K) return H;
  return { isInsideText: K };
}

This confirms an ink-box host element is being mounted while the parent context has isInsideText: true.

Reproduction

1. Start a Claude Code session with CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS=1.
2. Call TeamCreate to create a team.
3. Spawn a teammate via Agent(subagent_type=..., team_name=..., name=...) whose persona or spawn prompt encourages replies containing inline code formatting. (I reproduced with an agent whose spawn reply included the phrase `uv run python`, but any backtick-delimited inline code in the reply is sufficient.)
4. After the teammate sends its first reply to team-lead and goes idle, Claude Code renders the ※ recap: compact summary in the teammate's own pane.
5. At that render, the crash fires. Pane shows Ink error-boundary fallback (which, with tmux alternate-screen off, also mis-paints and dumps bundled cli.js source into the pane).
6. The whole team directory is torn down shortly after.

Expected: recap renders code spans inline, like the main message render does. Actual: Ink reconciler throws from createInstance, pane enters zombie state, team is torn down.

Root-cause hypothesis

The ※ recap: component structure appears to be:

<Text>
  ※ recap: <InlineMarkdown content={previewText}/>
</Text>

Where InlineMarkdown emits a <Box> wrapper for code spans (for background-color / padding visual treatment):

<Box backgroundColor="gray" paddingX={1}>
  <Text>uv run python</Text>
</Box>

The <Box> lands inside the outer <Text> wrapper → violates Ink's getChildHostContext invariant → throw.

Suggested fix

Two clean options:

Option A — change recap's outer wrapper from <Text> to <Box>, move prefix into inner <Text>:

// Buggy:
<Text>
  ※ recap: <InlineMarkdown content={preview}/>
</Text>

// Fixed:
<Box>
  <Text>※ recap: </Text>
  <InlineMarkdown content={preview}/>
</Box>

Option B — change the inline-code-span renderer to use <Text>-level styling instead of <Box> wrapping:

// Buggy:
<Box backgroundColor="gray" paddingX={1}><Text>{code}</Text></Box>

// Fixed:
<Text backgroundColor="gray"> {code} </Text>

Option B is probably more robust because it fixes the code-span component regardless of where it's used.

Evidence the bug is specific to recap rendering (not message receipt)

The main message render in team-lead's pane rendered the same backticked content correctly. Only the ※ recap: line in the teammate's own pane crashed. That points at a separate renderer path that wraps message content in a stricter container.

Selective-crash pattern across a 5-agent team

In one session, spawned 5 teammates. Only the two whose replies/received-content included backticks crashed:

Also: crash fires mid-render of the ※ recap: line specifically — ✶ Doing… / ✢ Doing… status lines (which lack backticks) rendered cleanly before the crash.

Amplifier (orthogonal, self-fixed)

If the user's ~/.tmux.conf has set-option -g alternate-screen off, the Ink error-boundary fallback mis-paints and dumps ~2000 lines of bundled cli.js source into the pane (reproduced this myself). With tmux's default alternate-screen on, the fallback renders a clean error screen. This is user-side config and not Claude Code's responsibility, but worth noting for anyone reproducing.

Related issues

• #49865 — getAppState is not a function crash on permission-prompt render. Different bug, fixed in v2.1.114. I initially wondered if they were related; they are not.

Workaround (current)

Include an explicit directive in teammate spawn prompts to ban backticks in SendMessage replies. Example: "NEVER use backticks, code fences, or inline code formatting in SendMessage content. Reference paths and identifiers as plain prose." This sidesteps the crash but is fragile (depends on agent compliance).