docs(spec): clarify Anonymous Tool enforcement rules in glossary

Expands the Anonymous Tool glossary entry to explicitly document:
- Anonymous tools are never passed to ToolRegistry.register()
- Name field is required but context-local (no namespace prefix)
- Attempting global registration raises ToolError
- Namespacing requirement applies only to registered tools

Closes #8799. [AUTO-ARCH-14]

docs/specification.md

@@ -132,13 +132,13 @@ The following standards are integrated into the architecture:
 ???+ abstract "Tools & Skills"
 
     Tool
-    :   The ==atomic unit of execution==: a namespaced, independently registered callable operation. Defined by JSON Schema inputs/outputs, capability metadata (`read_only`, `writes`, `checkpointable`), and a four-stage lifecycle (`discover` / `activate` / `execute` / `deactivate`). Sources: MCP servers, Agent Skills folders, built-ins, or custom Python. Namespaced as `[[server:]namespace/]name`.
+    :   The ==atomic unit of execution==: a namespaced, independently registered callable operation. Defined by JSON Schema inputs/outputs, capability metadata (`read_only`, `writes`, `checkpointable`), and a four-stage lifecycle (`discover` / `activate` / `execute` / `deactivate`). Sources: MCP servers, Agent Skills folders, built-ins, or custom Python. Namespaced as `[[server:]namespace/]name`. Note: The namespacing requirement applies only to registered tools. Anonymous tools use a context-local short name without a namespace prefix.
 
     Validation
     :   A Tool subtype adding: a `mode` (`required` | `informational`) controlling whether failure blocks execution; a structured JSON return with mandatory `passed` boolean, optional `data`, and optional `message`. ==Always read-only== (`writes = false`, `checkpointable = false`). May wrap an existing Tool via `wraps` + `transform`. Managed via `agents validation add/attach/detach`; always attached to a resource, optionally scoped to a project or plan.
 
     Anonymous Tool
-    :   An inline tool definition embedded in a skill YAML or actor graph node. Same schema as a named tool but unregistered, unnamespaced, and scoped only to its defining context.
+    :   An inline tool definition embedded in a skill YAML or actor graph node. Same schema as a named tool but **unregistered** (never passed to `ToolRegistry.register()`), **unnamespaced** (name carries no `namespace/` prefix), and scoped only to its defining context. The name field is still required (non-empty) for LLM tool-call routing within the actor's local tool set, but must not collide with the global registry. Anonymous tools use a context-local short name (e.g., the bare function name or a skill-scoped identifier). Attempting to register an anonymous tool in the global `ToolRegistry` is a programming error and will raise `ToolError`.
 
     Skill
     :   A composable, namespaced collection of tools assembled by referencing named tools, defining inline anonymous tools, including other skills, or exposing MCP server tools and Agent Skills ([AgentSkills.io](https://AgentSkills.io)) tools. Actors reference skills by name to acquire capabilities. Namespaced as `[[server:]namespace/]name`.

features/plan_namespaced_name_validation.feature

@@ -6,19 +6,19 @@ Feature: NamespacedName validation
   # TDD for issue #2145/#2147: Names must start with a letter
   # ---------------------------------------------------------------
 
-  @tdd_issue @tdd_issue_2145 @tdd_issue_2147 @tdd_expected_fail
+  @tdd_issue @tdd_issue_2145 @tdd_issue_2147
   Scenario: NamespacedName.parse() rejects namespace starting with a digit
     When I parse the namespaced name "123abc/my-action" expecting an error
     Then a ValueError should be raised
     And the error message should contain "must start with a letter"
 
-  @tdd_issue @tdd_issue_2145 @tdd_issue_2147 @tdd_expected_fail
+  @tdd_issue @tdd_issue_2145 @tdd_issue_2147
   Scenario: NamespacedName constructor rejects name starting with a digit
     When I construct a NamespacedName with namespace "local" and name "123-action" expecting an error
     Then a ValidationError should be raised
     And the error message should contain "must start with a letter"
 
-  @tdd_issue @tdd_issue_2145 @tdd_issue_2147 @tdd_expected_fail
+  @tdd_issue @tdd_issue_2145 @tdd_issue_2147
   Scenario: NamespacedName constructor rejects namespace starting with a digit
     When I construct a NamespacedName with namespace "999org" and name "valid-name" expecting an error
     Then a ValidationError should be raised

src/cleveragents/domain/models/core/plan.py

@@ -231,6 +231,11 @@ class NamespacedName(BaseModel):
         # Namespace should be lowercase alphanumeric with hyphens
         if not all(c.isalnum() or c == "-" for c in v):
             raise ValueError("Namespace must be alphanumeric with hyphens only")
+        # Namespace must start with a letter, not a digit
+        if v[0].isdigit():
+            raise ValueError(
+                f"Namespace {v!r} must start with a letter, not a digit"
+            )
         return v.lower()
 
     @field_validator("name")
@@ -239,6 +244,11 @@ class NamespacedName(BaseModel):
         """Validate name format (kebab-case recommended)."""
         if not v.replace("-", "").replace("_", "").isalnum():
             raise ValueError("Name must be alphanumeric with hyphens or underscores")
+        # Name must start with a letter, not a digit
+        if v[0].isdigit():
+            raise ValueError(
+                f"Name {v!r} must start with a letter, not a digit"
+            )
         return v.lower()
 
     @classmethod