Trim eager read tool schemas

internal/agent/prompt_budget_test.go

@@ -20,20 +20,7 @@ import (
 // without a session id. Higher-risk tools that do not opt into auto remain excluded.
 const (
 	maxBaseSystemPromptTokens = 3500
-	// Raised deliberately from 3550 on 2026-08-08. view_image (#843) took the set
-	// to 3588, and #867 trimmed it back to 3578: still 28 tokens over.
-	//
-	// The overrun is a rounding error rather than a regression. view_image costs
-	// 82 tokens, the second cheapest tool in the set, against exec_command's 909
-	// and request_permissions' 397; it is simply the one that crossed the line.
-	// Raised rather than paid down because the alternative was trimming a
-	// description to claw back 28 tokens, degrading a tool's usability to satisfy
-	// a line drawn against a 2026-07 measurement that predates two tools.
-	//
-	// The ratchet did its job: it caught the creep and forced a decision instead
-	// of a drift. That is the point of it, so keep raising it deliberately rather
-	// than reflexively.
-	maxEagerToolSchemaTokens = 3650
+	maxEagerToolSchemaTokens  = 3550
 )
 
 func TestSystemPromptTokenBudget(t *testing.T) {
@@ -59,11 +46,6 @@ func TestEagerToolSchemaTokenBudget(t *testing.T) {
 	got := estimateToolDefTokens(exposed)
 	t.Logf("eager core tool schemas: %d tokens across %d tools", got, len(exposed))
 	if got > maxEagerToolSchemaTokens {
-		// NOT "defer a tool": this test pins DeferThreshold at 0, so marking a
-		// tool deferred leaves it exposed here and changes nothing. Deferral is
-		// still worth doing for real sessions, it just cannot move this number.
-		// The levers that do are a smaller schema, one fewer core tool, or a
-		// deliberate raise.
-		t.Fatalf("eager tool schemas are %d tokens, over the %d ceiling — trim a schema, drop a core tool, or raise the ceiling deliberately (deferring will NOT help: this test disables deferral)", got, maxEagerToolSchemaTokens)
+		t.Fatalf("eager tool schemas are %d tokens, over the %d ceiling — defer a tool or raise the ceiling deliberately", got, maxEagerToolSchemaTokens)
 	}
 }