chenhg5/cc-connect · warning

text exceeds max_text_len (%d > %d)

Error message

text exceeds max_text_len (%d > %d)

What it means

When TTS is configured, synthesizeAndSendTTS enforces an optional per-request text length limit: if tts.max_text_len > 0 and the reply text has more runes than that limit, synthesis is refused with this error naming both the actual and maximum rune counts.

Source

Thrown at core/engine.go:15875

// sendTTSReply synthesizes fullResponse text and sends audio to the platform.
// Called asynchronously after EventResult; text reply is always sent first.
func (e *Engine) sendTTSReply(p Platform, replyCtx any, text string) {
	slog.Debug("tts: sendTTSReply called", "platform", p.Name(), "text_len", len(text))
	if err := e.synthesizeAndSendTTS(p, replyCtx, text); err != nil {
		slog.Error("tts: voice reply failed", "platform", p.Name(), "error", err)
	}
}

func (e *Engine) synthesizeAndSendTTS(p Platform, replyCtx any, text string) error {
	if e.tts == nil || !e.tts.Enabled {
		return fmt.Errorf("tts is not configured")
	}
	if e.tts.TTS == nil {
		return fmt.Errorf("tts provider is not configured")
	}
	if e.tts.MaxTextLen > 0 && utf8.RuneCountInString(text) > e.tts.MaxTextLen {
		return fmt.Errorf("text exceeds max_text_len (%d > %d)", utf8.RuneCountInString(text), e.tts.MaxTextLen)
	}
	as, ok := p.(AudioSender)
	if !ok {
		return fmt.Errorf("platform %s does not support audio sending", p.Name())
	}
	slog.Info("tts: starting synthesis", "voice", e.tts.Voice, "speed", e.tts.Speed, "text_len", len(text))
	opts := TTSSynthesisOpts{
		Voice:        e.tts.Voice,
		LanguageType: e.tts.LanguageType,
		Speed:        e.tts.Speed,
	}
	audioData, format, err := e.tts.TTS.Synthesize(e.ctx, StripMarkdown(text), opts)
	if err != nil {
		return fmt.Errorf("synthesize: %w", err)
	}
	slog.Info("tts: synthesis successful", "format", format, "audio_size", len(audioData))
	if err := as.SendAudio(e.ctx, replyCtx, audioData, format); err != nil {
		return fmt.Errorf("send audio: %w", err)

View on GitHub (pinned to 4000b2338a)

Solutions

1. Increase tts.max_text_len in config.toml (or remove it to disable the cap) and reload
2. Truncate or summarize the text to fit within max_text_len before requesting TTS
3. Send the long content as a text/file message instead of voice

Example fix

// before (config.toml)
[tts]
enabled = true
max_text_len = 200
// after
[tts]
enabled = true
max_text_len = 2000

if e.TTSMaxTextLen() > 0 && utf8.RuneCountInString(text) > e.TTSMaxTextLen() {
    text = truncateRunes(text, e.TTSMaxTextLen())
}

if err := e.SynthesizeAndSendTTS(p, replyCtx, text); err != nil {
    if strings.Contains(err.Error(), "exceeds max_text_len") {
        p.Reply(replyCtx, text) // send as text instead
        return
    }
    return err
}

When it happens

Trigger: Requesting a voice reply for text whose UTF-8 rune count exceeds tts.max_text_len, e.g. asking the agent to speak a long code answer when max_text_len = 500.

Common situations: Long agent responses sent as voice; conservative max_text_len values set to control provider cost; multilingual text where users underestimate rune counts.

Understand the failure class

Background: payload too large / request exceeds maximum size: why libraries cap bytes and how to fix oversize payloads — this error's family across 50 libraries.

Related errors

• hook input exceeds %d bytes
• Content-Length too large: %d
• download exceeds --max-bytes: %d > %d
• tts is not configured
• tts provider is not configured

AI-assisted analysis of chenhg5/cc-connect@4000b2338a (2026-09-06). Data as JSON: /api/errors/01dc5c8efdff8f42. Report an issue: GitHub.