hermes-agent/tests/tools/test_tts_max_text_length.py
Teknium 8f167e8791
fix(tts): use per-provider input-character caps instead of global 4000 (#13743)
A single global MAX_TEXT_LENGTH = 4000 truncated every TTS provider at
4000 chars, causing long inputs to be silently chopped even though the
underlying APIs allow much more:

  - OpenAI:     4096
  - xAI:        15000
  - MiniMax:    10000
  - ElevenLabs: 5000 / 10000 / 30000 / 40000 (model-aware)
  - Gemini:     ~5000
  - Edge:       ~5000

The schema description also told the model 'Keep under 4000 characters',
which encouraged the agent to self-chunk long briefs into multiple TTS
calls (producing 3 separate audio files instead of one).

New behavior:
  - PROVIDER_MAX_TEXT_LENGTH table + ELEVENLABS_MODEL_MAX_TEXT_LENGTH
    encode the documented per-provider limits.
  - _resolve_max_text_length(provider, cfg) resolves:
      1. tts.<provider>.max_text_length user override
      2. ElevenLabs model_id lookup
      3. provider default
      4. 4000 fallback
  - text_to_speech_tool() and stream_tts_to_speaker() both call the
    resolver; old MAX_TEXT_LENGTH alias kept for back-compat.
  - Schema description no longer hardcodes 4000.

Tests: 27 new unit + E2E tests; all 53 existing TTS tests and 253
voice-command/voice-cli tests still pass.
2026-04-21 17:49:39 -07:00

197 lines
7.7 KiB
Python

"""Tests for per-provider TTS input-character limits.
Replaces the old global ``MAX_TEXT_LENGTH = 4000`` cap that truncated every
provider at 4000 chars even though OpenAI allows 4096, xAI allows 15000,
MiniMax allows 10000, and ElevenLabs allows 5000-40000 depending on model.
"""
import json
from unittest.mock import patch
import pytest
from tools.tts_tool import (
ELEVENLABS_MODEL_MAX_TEXT_LENGTH,
FALLBACK_MAX_TEXT_LENGTH,
PROVIDER_MAX_TEXT_LENGTH,
_resolve_max_text_length,
)
class TestResolveMaxTextLength:
def test_edge_default(self):
assert _resolve_max_text_length("edge", {}) == PROVIDER_MAX_TEXT_LENGTH["edge"]
def test_openai_default_is_4096(self):
assert _resolve_max_text_length("openai", {}) == 4096
def test_xai_default_is_15000(self):
assert _resolve_max_text_length("xai", {}) == 15000
def test_minimax_default_is_10000(self):
assert _resolve_max_text_length("minimax", {}) == 10000
def test_mistral_default(self):
assert _resolve_max_text_length("mistral", {}) == PROVIDER_MAX_TEXT_LENGTH["mistral"]
def test_gemini_default(self):
assert _resolve_max_text_length("gemini", {}) == PROVIDER_MAX_TEXT_LENGTH["gemini"]
def test_unknown_provider_falls_back(self):
assert _resolve_max_text_length("does-not-exist", {}) == FALLBACK_MAX_TEXT_LENGTH
def test_empty_provider_falls_back(self):
assert _resolve_max_text_length("", {}) == FALLBACK_MAX_TEXT_LENGTH
assert _resolve_max_text_length(None, {}) == FALLBACK_MAX_TEXT_LENGTH
def test_case_insensitive(self):
assert _resolve_max_text_length("OpenAI", {}) == 4096
assert _resolve_max_text_length(" XAI ", {}) == 15000
# --- Overrides ---
def test_override_wins(self):
cfg = {"openai": {"max_text_length": 9999}}
assert _resolve_max_text_length("openai", cfg) == 9999
def test_override_zero_falls_through(self):
# A broken/zero override must not disable truncation
cfg = {"openai": {"max_text_length": 0}}
assert _resolve_max_text_length("openai", cfg) == 4096
def test_override_negative_falls_through(self):
cfg = {"xai": {"max_text_length": -1}}
assert _resolve_max_text_length("xai", cfg) == 15000
def test_override_non_int_falls_through(self):
cfg = {"minimax": {"max_text_length": "lots"}}
assert _resolve_max_text_length("minimax", cfg) == 10000
def test_override_bool_falls_through(self):
# bool is technically an int; make sure we don't treat True as 1 char
cfg = {"openai": {"max_text_length": True}}
assert _resolve_max_text_length("openai", cfg) == 4096
def test_missing_provider_section_uses_default(self):
cfg = {"provider": "openai"} # no "openai" key
assert _resolve_max_text_length("openai", cfg) == 4096
# --- ElevenLabs model-aware ---
def test_elevenlabs_default_model_multilingual_v2(self):
cfg = {"elevenlabs": {"model_id": "eleven_multilingual_v2"}}
assert _resolve_max_text_length("elevenlabs", cfg) == 10000
def test_elevenlabs_flash_v2_5_gets_40k(self):
cfg = {"elevenlabs": {"model_id": "eleven_flash_v2_5"}}
assert _resolve_max_text_length("elevenlabs", cfg) == 40000
def test_elevenlabs_flash_v2_gets_30k(self):
cfg = {"elevenlabs": {"model_id": "eleven_flash_v2"}}
assert _resolve_max_text_length("elevenlabs", cfg) == 30000
def test_elevenlabs_v3_gets_5k(self):
cfg = {"elevenlabs": {"model_id": "eleven_v3"}}
assert _resolve_max_text_length("elevenlabs", cfg) == 5000
def test_elevenlabs_unknown_model_falls_back_to_provider_default(self):
cfg = {"elevenlabs": {"model_id": "eleven_experimental_xyz"}}
assert _resolve_max_text_length("elevenlabs", cfg) == PROVIDER_MAX_TEXT_LENGTH["elevenlabs"]
def test_elevenlabs_override_beats_model_lookup(self):
cfg = {"elevenlabs": {"model_id": "eleven_flash_v2_5", "max_text_length": 1000}}
assert _resolve_max_text_length("elevenlabs", cfg) == 1000
def test_elevenlabs_no_model_id_uses_default_model_mapping(self):
# Falls back to DEFAULT_ELEVENLABS_MODEL_ID = eleven_multilingual_v2 -> 10000
assert _resolve_max_text_length("elevenlabs", {}) == 10000
def test_provider_config_not_a_dict(self):
cfg = {"openai": "not-a-dict"}
assert _resolve_max_text_length("openai", cfg) == 4096
# --- Sanity: the table covers every provider listed in the schema ---
def test_all_documented_providers_have_defaults(self):
expected = {"edge", "openai", "xai", "minimax", "mistral",
"gemini", "elevenlabs", "neutts", "kittentts"}
assert expected.issubset(PROVIDER_MAX_TEXT_LENGTH.keys())
class TestTextToSpeechToolTruncation:
"""End-to-end: verify the resolver actually drives the text_to_speech_tool
truncation path rather than the old 4000-char global."""
def test_openai_truncates_at_4096_not_4000(self, tmp_path, monkeypatch, caplog):
import logging
caplog.set_level(logging.WARNING, logger="tools.tts_tool")
# 5000 chars -- over OpenAI's 4096 limit but under xAI's 15k
text = "A" * 5000
captured_text = {}
def fake_openai(t, out, cfg):
captured_text["text"] = t
with open(out, "wb") as f:
f.write(b"\x00")
return out
monkeypatch.setattr("tools.tts_tool._generate_openai_tts", fake_openai)
monkeypatch.setattr("tools.tts_tool._load_tts_config",
lambda: {"provider": "openai"})
from tools.tts_tool import text_to_speech_tool
out = str(tmp_path / "out.mp3")
result = json.loads(text_to_speech_tool(text=text, output_path=out))
assert result["success"] is True
# Should be truncated to 4096, not the old 4000
assert len(captured_text["text"]) == 4096
# And the warning should mention the provider
assert any("openai" in rec.message.lower() for rec in caplog.records)
def test_xai_accepts_much_longer_input(self, tmp_path, monkeypatch):
# 12000 chars -- over old global 4000, under xAI's 15000
text = "B" * 12000
captured_text = {}
def fake_xai(t, out, cfg):
captured_text["text"] = t
with open(out, "wb") as f:
f.write(b"\x00")
return out
monkeypatch.setattr("tools.tts_tool._generate_xai_tts", fake_xai)
monkeypatch.setattr("tools.tts_tool._load_tts_config",
lambda: {"provider": "xai"})
from tools.tts_tool import text_to_speech_tool
out = str(tmp_path / "out.mp3")
result = json.loads(text_to_speech_tool(text=text, output_path=out))
assert result["success"] is True
# xAI should accept the full 12000 chars
assert len(captured_text["text"]) == 12000
def test_user_override_is_respected(self, tmp_path, monkeypatch):
# User says "cap openai at 100 chars" -- we must honor it
text = "C" * 500
captured_text = {}
def fake_openai(t, out, cfg):
captured_text["text"] = t
with open(out, "wb") as f:
f.write(b"\x00")
return out
monkeypatch.setattr("tools.tts_tool._generate_openai_tts", fake_openai)
monkeypatch.setattr("tools.tts_tool._load_tts_config",
lambda: {"provider": "openai",
"openai": {"max_text_length": 100}})
from tools.tts_tool import text_to_speech_tool
out = str(tmp_path / "out.mp3")
result = json.loads(text_to_speech_tool(text=text, output_path=out))
assert result["success"] is True
assert len(captured_text["text"]) == 100