Two bugs surfaced from production usage in #37134:
1. Dict choices rendered as Python repr. LLMs sometimes emit
[{"description": "..."}] instead of bare strings; the old
str(c).strip() coercion turned the whole dict into
"{'description': '...'}" on the button label.
Fix: add a _flatten_choice helper that unwraps dicts against
the canonical LLM tool-call user-facing keys (label, description,
text, title) in that order. Dicts with none of those keys are
dropped. The "name" and "value" keys are deliberately NOT in the
priority list — they're Discord-component-shaped fields that
could appear in dicts that aren't meant to be choices (a
developer-error wiring that passes a Button-shaped object);
picking them would leak raw enum values or 4-char model
identifiers onto user-facing buttons.
2. Mid-word truncation on long button labels. The old
choice[:72] + "..." cut at position 72, mid-word. Worse, the
three-char ellipsis ate into the 80-char Discord label cap,
leaving only 75 chars of body.
Fix: budget-aware cut strategy with three tiers:
a. Last space in the trailing half of the budget (word boundary).
b. Last soft boundary (- , . )) in the trailing half — used
only when no word boundary exists.
c. Hard cut at the budget limit (last resort).
Use single U+2026 (…) to fit the cap. Cut AT soft boundaries
(inclusive) so the label ends on the boundary char rather than
on the alpha char that followed it.
Tests:
- test_unwraps_dict_choices_to_description: reproduces the
screenshot in #37134, asserts the Python repr is gone.
- test_unwrap_prefers_description_over_name_in_multi_key_dict:
regression guard for the name-key order in the unwrap list.
- test_unwrap_prefers_label_over_description: regression guard
for label winning over description.
- test_unwrap_does_not_pick_value_or_name_alone: regression
guard for the "name"/"value" fields being absent.
- test_truncates_long_choice_label: 200-char input, asserts
total <= 80 and U+2026.
- test_truncates_long_choice_label_breaks_on_word_boundary:
asserts the cut is on a space, not mid-word.
- test_truncates_long_no_space_choice_on_soft_boundary:
adversarial input where position 76 is mid-word alpha, asserts
the renderer falls back to a soft boundary.
Parity: telegram clarify suite (12 tests) still passes; the
helper is a Discord adapter local, not shared with the gateway.
Follow-up: gateway/platforms/telegram.py has the same str(c).strip()
pattern in its own send_clarify and will need a similar fix
(separate PR to keep this diff reviewable).
Fixes#37134
bce1e36b57