fix(agents): coerce a non-string description in TOML command rendering (#3799)

CommandRegistrar.render_toml_command passes the raw frontmatter `description`
straight into `_render_basic_toml_string`, which iterates the value and calls
ord() on each character. Frontmatter comes from yaml.safe_load, so description
can be any YAML type:

    description='ok string' -> description = "ok string"
    description=None        -> TypeError: 'NoneType' object is not iterable
    description=42          -> TypeError: 'int' object is not iterable
    description=True        -> TypeError: 'bool' object is not iterable
    description=['a','b']   -> description = "ab"     <- silently WRONG value

This is a format-branch asymmetry: it is the only renderer reached from
register_commands' format branches that does not normalise description.
render_yaml_command (same class, ~70 lines below) already does exactly
`if not isinstance(description, str): description = str(description) if
description is not None else ""`, render_markdown_command goes through
yaml.dump which handles any type, and TomlIntegration._extract_description
returns "" for a non-str. So only extension/preset commands rendered for the two
TOML agents were affected.

Apply the same coercion the sibling uses. After: None -> "", 42 -> "42",
True -> "True", ['a','b'] -> "['a', 'b']", each still valid parseable TOML.
String descriptions are untouched.

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

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/specify_cli/agents.py

@@ -302,8 +302,20 @@ class CommandRegistrar:
         toml_lines = []
 
         if "description" in frontmatter:
+            # Frontmatter comes from ``yaml.safe_load``, so ``description`` can
+            # be any YAML type: ``description:`` with no value yields None,
+            # ``description: 2`` an int, an unquoted ``true`` a bool.
+            # ``_render_basic_toml_string`` iterates the value and calls ord()
+            # on each character, so a non-string raises a raw TypeError -- and a
+            # list of single-character items is silently concatenated into a
+            # wrong value (``["a", "b"]`` -> ``"ab"``). Coerce first, matching
+            # ``render_yaml_command`` below and ``TomlIntegration
+            # ._extract_description``, which both normalise it already.
+            description = frontmatter["description"]
+            if not isinstance(description, str):
+                description = str(description) if description is not None else ""
             toml_lines.append(
-                f"description = {self._render_basic_toml_string(frontmatter['description'])}"
+                f"description = {self._render_basic_toml_string(description)}"
             )
             toml_lines.append("")
 

tests/test_extensions.py

@@ -2720,6 +2720,36 @@ Real body starts here.
 
         assert parsed["description"] == "first line\nsecond line\n"
 
+    @pytest.mark.parametrize(
+        ("description", "expected"),
+        [
+            (None, ""),                    # "description:" with no value
+            (42, "42"),                    # unquoted number
+            (True, "True"),                # unquoted boolean
+            (["a", "b"], "['a', 'b']"),    # was silently concatenated to "ab"
+        ],
+    )
+    def test_render_toml_command_coerces_non_string_description(
+        self, description, expected
+    ):
+        """Frontmatter comes from yaml.safe_load, so description can be any type.
+
+        _render_basic_toml_string iterates the value and calls ord() per
+        character, so a non-string raised a raw TypeError and a list of
+        single-character items was silently concatenated into a wrong value.
+        render_yaml_command (same class) already coerces; this brings the TOML
+        branch to parity.
+        """
+        from specify_cli.agents import CommandRegistrar as AgentCommandRegistrar
+
+        registrar = AgentCommandRegistrar()
+        output = registrar.render_toml_command(
+            {"description": description}, "body", "extension:test-ext"
+        )
+
+        parsed = tomllib.loads(output)
+        assert parsed["description"] == expected
+
     def test_render_toml_command_escapes_control_characters(self):
         """Control characters and a lone CR must be escaped so the TOML parses.