feat(mcp): state the structural questions in the scout and analysis profiles

The read-only analysis profile and the fast scout profile serve the graph
subagents (codebase-memory-auditor, codebase-memory-scout). Their server
instructions listed tools only. Like the default profile, they now state as
facts which structural questions the graph answers (where a symbol is defined,
who calls a function, what it calls, and for analysis also call chains, data
flow and change impact), keywords first: analysis 190 -> 648 characters, scout
199 -> 427, well within Claude Code's 4,096-character cut. The profile names,
check_index_coverage and the absence of index_repository are unchanged.

Stacked on #2698.

Refs #509

Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>

Author: DeusData

src/mcp/mcp.c

@@ -1473,14 +1473,22 @@ static const char MCP_SERVER_INSTRUCTIONS[] =
     "Results are paginated.";
 
 static const char MCP_ANALYSIS_SERVER_INSTRUCTIONS[] =
-    "analysis tool profile: read-only graph work via search_graph, trace_path, "
-    "get_code_snippet, query_graph, get_architecture, or search_code. Use check_index_coverage "
-    "for cited paths; paginate.";
+    "analysis tool profile (read-only): a code knowledge graph of the indexed repository for "
+    "structural questions: where a symbol is defined, who calls a function, what it calls, call "
+    "chains and data flow, which code a change affects, how modules fit together. search_graph "
+    "finds symbols; trace_path follows callers, callees and data flow; get_code_snippet returns "
+    "exact source; query_graph runs multi-hop Cypher; get_architecture summarizes structure; "
+    "search_code combines text search with graph context; detect_changes maps the current diff "
+    "to affected symbols. check_index_coverage tells whether a cited file was fully indexed. "
+    "Results are paginated.";
 
 static const char MCP_SCOUT_SERVER_INSTRUCTIONS[] =
-    "scout tool profile: fast positive discovery via search_graph, trace_path, "
-    "get_code_snippet, or get_architecture with narrow limits. Use check_index_coverage for "
-    "cited paths. Findings are provisional.";
+    "scout tool profile (fast, provisional): quick structural lookups in the indexed "
+    "repository: where a symbol is defined, who calls a function, what it calls. search_graph "
+    "finds symbols; trace_path follows callers and callees; get_code_snippet returns exact "
+    "source; get_architecture summarizes structure; narrow limits keep answers fast. "
+    "check_index_coverage tells whether a cited file was fully indexed. Findings are "
+    "provisional.";
 
 static char *cbm_mcp_initialize_response_for_profile(const char *params_json,
                                                      cbm_mcp_tool_profile_t profile) {

tests/test_mcp.c

@@ -2195,6 +2195,9 @@ TEST(server_handle_analysis_profile_filters_and_rejects_mutators) {
     ASSERT_NOT_NULL(strstr(resp, "analysis tool profile"));
     ASSERT_NOT_NULL(strstr(resp, "check_index_coverage"));
     ASSERT_NULL(strstr(resp, "index_repository"));
+    /* Profile instructions name the structural questions, like the default. */
+    ASSERT_NOT_NULL(strstr(resp, "who calls a function"));
+    ASSERT_NOT_NULL(strstr(resp, "which code a change affects"));
     free(resp);
 
     resp = cbm_mcp_server_handle(srv, "{\"jsonrpc\":\"2.0\",\"id\":220,\"method\":\"tools/list\"}");
@@ -2237,6 +2240,7 @@ TEST(server_handle_scout_profile_exposes_only_the_fast_tier) {
     ASSERT_NOT_NULL(strstr(resp, "scout tool profile"));
     ASSERT_NOT_NULL(strstr(resp, "check_index_coverage"));
     ASSERT_NULL(strstr(resp, "index_repository"));
+    ASSERT_NOT_NULL(strstr(resp, "who calls a function"));
     ASSERT_FALSE(mcp_saw_autoindex_log);
     free(resp);