From ed01ac999408fd3b3109785eacbbf430d3bf039f Mon Sep 17 00:00:00 2001
From: Tim Wang <38489718+wanghualoong@users.noreply.github.com>
Date: Mon, 11 May 2026 10:01:41 +0800
Subject: [PATCH] Fix: resolve template strings in tool component parameters
 (#14601)
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## Summary

- Tool-type components (Email, Invoke, etc.) fail to resolve template
strings that mix variable references with literal text in their
parameters.
- This adds template string resolution to `get_input()` in
`ComponentBase`, reusing existing `get_input_elements_from_text()` and
`string_format()` methods.

## Problem

`get_input()` in `ComponentBase` handles two cases:
1. **Pure reference** (`{Component:ID@field}`) — resolved via
`is_reff()` + `get_variable_value()`
2. **Literal value** — passed through as-is

But template strings like `{UserFillUp:X@name}@duke.edu` or `Question
from {Agent:Y@topic}` fall through to the literal branch because
`is_reff()` returns `False` (it expects the entire string to be a single
reference). The unresolved template is passed directly to the tool.

This affects **all** tool components (Email, Invoke, etc.) that need
mixed reference + text parameters — for example, constructing email
addresses or subjects dynamically.

## Fix

```python
# In get_input(), between is_reff check and literal fallback:
elif isinstance(v, str) and re.search(self.variable_ref_patt, v):
    elements = self.get_input_elements_from_text(v)
    kv = {k: e.get('value', '') for k, e in elements.items()}
    self.set_input_value(var, self.string_format(v, kv))
```

This reuses `get_input_elements_from_text()` and `string_format()` which
are already used by `Message` components for the same purpose. The fix
only activates when the string contains at least one variable reference
pattern but is not a pure reference.

## Test plan

- [x] Pure references (`{Component:ID@field}`) still resolve correctly
via `is_reff()` path
- [x] Literal values without references pass through unchanged
- [x] Template strings like `{ref}@duke.edu` resolve the reference and
keep the literal suffix
- [x] Template strings like `Question from {ref}` resolve correctly
- [x] Multiple references in one string (`{ref1} and {ref2}`) both
resolve
- [x] Message components unaffected (they use their own template
resolution in `_run`)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: wanghualoong <wanghualoong@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
---
 agent/component/base.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/agent/component/base.py b/agent/component/base.py
index 9bceb4ce6..1acfa773d 100644
--- a/agent/component/base.py
+++ b/agent/component/base.py
@@ -486,6 +486,10 @@ class ComponentBase(ABC):
                 continue
             if isinstance(v, str) and self._canvas.is_reff(v):
                 self.set_input_value(var, self._canvas.get_variable_value(v))
+            elif isinstance(v, str) and re.search(self.variable_ref_patt, v):
+                elements = self.get_input_elements_from_text(v)
+                kv = {k: e.get('value', '') for k, e in elements.items()}
+                self.set_input_value(var, self.string_format(v, kv))
             else:
                 self.set_input_value(var, v)
             res[var] = self.get_input_value(var)