refactor(tools): simplify collapsed tool prompts and stub schema

src/crates/assembly/core/src/agentic/agents/prompt_builder/prompt_builder_impl.rs

@@ -751,8 +751,7 @@ mod tests {
             skill_listing: Some("<available_skills>\n- pdf\n</available_skills>".to_string()),
             agent_listing: Some("<available_agents>\n- Explore\n</available_agents>".to_string()),
             collapsed_tool_listing: Some(
-                "<collapsed_tools>\n- WebFetch: Fetch readable web content.\n</collapsed_tools>"
-                    .to_string(),
+                "<collapsed_tools>\n- WebFetch\n</collapsed_tools>".to_string(),
             ),
         };
         let context = PromptBuilderContext::new(r"workspace\root", None, None)

src/crates/assembly/core/src/agentic/tools/product_runtime/catalog.rs

@@ -562,18 +562,13 @@ mod tests {
                 .unwrap_or_else(|| panic!("{tool_name} stub should exist"));
             assert!(
                 stub.description.contains(&format!(
-                    "First call `GetToolSpec` with {{\"tool_name\":\"{tool_name}\"}}"
+                    "Call `GetToolSpec` with {{\"tool_name\":\"{tool_name}\"}} before first use."
                 )),
                 "collapsed stub must point to the explicit GetToolSpec unlock flow"
             );
             assert_eq!(stub.parameters["type"], json!("object"));
             assert_eq!(stub.parameters["additionalProperties"], json!(false));
-            assert_eq!(
-                stub.parameters["properties"]["tool_name"]["description"],
-                json!(format!(
-                    "Do not supply {tool_name} arguments here while the tool is collapsed. Use GetToolSpec with {{\"tool_name\":\"{tool_name}\"}} first."
-                ))
-            );
+            assert_eq!(stub.parameters["properties"], json!({}));
         }
     }
 

src/crates/assembly/core/src/agentic/tools/product_runtime/get_tool_spec_tool.rs

@@ -9,16 +9,11 @@ use crate::agentic::tools::tool_context_runtime::ToolUseContext;
 use crate::util::errors::{BitFunError, BitFunResult};
 use async_trait::async_trait;
 use bitfun_agent_tools::{
-    build_get_tool_spec_collapsed_tool_entry, GetToolSpecCollapsedToolSummary,
-    GetToolSpecExecutionError, GET_TOOL_SPEC_TOOL_NAME,
+    GetToolSpecCollapsedToolSummary, GetToolSpecExecutionError, GET_TOOL_SPEC_TOOL_NAME,
 };
 use serde_json::Value;
 
-const GET_TOOL_SPEC_DESCRIPTION: &str = r#"Read usage instructions for additional tools.
-
-Some tools are collapsed: their names may appear in the tool list, but you must not call them directly until you have loaded their definition with GetToolSpec.
-
-When the current collapsed tool listing includes a <collapsed_tools> section, use the exact tool names from that section. Before using one of those tools, first call GetToolSpec with its exact tool name to read its full description and input schema. After reading the returned definition, call the real tool directly using its own name.
+const GET_TOOL_SPEC_DESCRIPTION: &str = r#"Read full schema before first calling a collapsed tool.
 
 Do not call GetToolSpec again for a tool whose definition is already loaded in the current conversation."#;
 
@@ -38,9 +33,7 @@ impl GetToolSpecTool {
 
         let collapsed_tools_list = collapsed_tools
             .iter()
-            .map(|tool| {
-                build_get_tool_spec_collapsed_tool_entry(&tool.name, &tool.short_description)
-            })
+            .map(|tool| format!("- {}", tool.name))
             .collect::<Vec<_>>()
             .join("\n");
 
@@ -139,7 +132,7 @@ mod tests {
     use std::collections::HashMap;
 
     #[test]
-    fn collapsed_tools_context_uses_explicit_short_description() {
+    fn collapsed_tools_context_lists_names_without_short_descriptions() {
         let tool_name = format!("CatalogDescriptionTestTool_{}", uuid::Uuid::new_v4());
         let description = GetToolSpecTool::build_collapsed_tools_context_section(&[
             bitfun_agent_tools::GetToolSpecCollapsedToolSummary {
@@ -149,8 +142,8 @@ mod tests {
         ])
         .expect("collapsed tools section");
 
-        assert!(description.contains(&format!("- {}: Concise catalog entry.", tool_name)));
-        assert!(!description.contains(&format!("- {}: Verbose description first line.", tool_name)));
+        assert!(description.contains(&format!("- {}", tool_name)));
+        assert!(!description.contains("Concise catalog entry."));
     }
 
     #[tokio::test]

src/crates/execution/agent-runtime/src/prompt.rs

@@ -7,7 +7,7 @@ const AGENT_LISTING_TITLE: &str = "# Agent Listing";
 const AGENT_LISTING_GUIDANCE: &str = "Available subagent types for the Task tool:";
 const COLLAPSED_TOOL_LISTING_TITLE: &str = "# Collapsed Tool Listing";
 const COLLAPSED_TOOL_LISTING_GUIDANCE: &str = r#"The folling tools are intentionally collapsed. Their listed descriptions are short summaries rather than full usage instructions.
-Before calling a collapsed tool, call `GetToolSpec` with its exact tool name to read its full definition and input schema.
+Before calling a collapsed tool, call `GetToolSpec` with its exact tool name to read its full schema.
 After reading the returned spec, call the real tool directly by its own name.
 If a tool spec is already available in the current conversation, do not call `GetToolSpec` for it again."#;
 

src/crates/execution/tool-contracts/src/framework.rs

@@ -309,22 +309,13 @@ pub fn build_collapsed_tool_stub_definition(
     ToolManifestDefinition::new(
         tool_name,
         format!(
-            "{} [This tool is collapsed. Do not call `{}` directly yet. First call `GetToolSpec` with {{\"tool_name\":\"{}\"}} to load its full description and input schema, then retry `{}` using the returned schema.]",
-            short_description, tool_name, tool_name, tool_name
+            "{} [This tool is collapsed. Call `GetToolSpec` with {{\"tool_name\":\"{}\"}} before first use.]",
+            short_description, tool_name,
         ),
         serde_json::json!({
             "type": "object",
             "additionalProperties": false,
-            "properties": {
-                "tool_name": {
-                    "type": "string",
-                    "description": format!(
-                        "Do not supply {} arguments here while the tool is collapsed. Use GetToolSpec with {{\"tool_name\":\"{}\"}} first.",
-                        tool_name,
-                        tool_name
-                    )
-                }
-            }
+            "properties": {}
         }),
     )
 }

src/crates/execution/tool-contracts/tests/tool_contracts.rs

@@ -1253,18 +1253,13 @@ fn collapsed_tool_stub_definition_preserves_prompt_visible_guardrail() {
     assert!(stub.description.contains("Fetch a URL"));
     assert!(stub
         .description
-        .contains("First call `GetToolSpec` with {\"tool_name\":\"WebFetch\"}"));
+        .contains("Call `GetToolSpec` with {\"tool_name\":\"WebFetch\"} before first use."));
     assert_eq!(
         stub.parameters,
         json!({
             "type": "object",
             "additionalProperties": false,
-            "properties": {
-                "tool_name": {
-                    "type": "string",
-                    "description": "Do not supply WebFetch arguments here while the tool is collapsed. Use GetToolSpec with {\"tool_name\":\"WebFetch\"} first."
-                }
-            }
+            "properties": {}
         })
     );
 }
@@ -1323,7 +1318,7 @@ fn prompt_visible_manifest_builder_preserves_expanded_and_collapsed_contract() {
     );
     assert!(definitions[2]
         .description
-        .contains("First call `GetToolSpec` with {\"tool_name\":\"WebFetch\"}"));
+        .contains("Call `GetToolSpec` with {\"tool_name\":\"WebFetch\"} before first use."));
 }
 
 #[test]
@@ -2199,7 +2194,7 @@ async fn contextual_manifest_resolver_preserves_runtime_visible_manifest_contrac
         .expect("collapsed WebFetch stub");
     assert!(web_fetch
         .description
-        .contains("First call `GetToolSpec` with {\"tool_name\":\"WebFetch\"}"));
+        .contains("Call `GetToolSpec` with {\"tool_name\":\"WebFetch\"} before first use."));
     assert_eq!(web_fetch.parameters["additionalProperties"], false);
 }