diff --git a/evals/frugalSearch.eval.ts b/evals/frugalSearch.eval.ts
index e4f3e85956a..11c51e85298 100644
--- a/evals/frugalSearch.eval.ts
+++ b/evals/frugalSearch.eval.ts
@@ -7,6 +7,11 @@
 import { describe, expect } from 'vitest';
 import { evalTest } from './test-helper.js';
 
+/**
+ * Evals to verify that the agent uses search tools efficiently (frugally)
+ * by utilizing limiting parameters like `total_max_matches` and `max_matches_per_file`.
+ * This ensures the agent doesn't flood the context window with unnecessary search results.
+ */
 describe('Frugal Search', () => {
   const getGrepParams = (call: any): any => {
     let args = call.toolRequest.args;
@@ -112,21 +117,26 @@ describe('Frugal Search', () => {
 
       expect(grepCalls.length).toBeGreaterThan(0);
 
-      const hasFrugalLimit = grepCalls.some((call) => {
-        const params = getGrepParams(call);
-        // Check for explicitly set small limit for "sample" or "example" requests
-        return (
-          params.total_max_matches !== undefined &&
-          params.total_max_matches <= 100
-        );
-      });
+      const grepParams = grepCalls.map(getGrepParams);
+
+      const hasTotalMaxLimit = grepParams.some(
+        (p) => p.total_max_matches !== undefined && p.total_max_matches <= 100,
+      );
+      expect(
+        hasTotalMaxLimit,
+        `Expected agent to use a small total_max_matches (<= 100) for a sample usage request. Actual values: ${JSON.stringify(
+          grepParams.map((p) => p.total_max_matches),
+        )}`,
+      ).toBe(true);
 
+      const hasMaxMatchesPerFileLimit = grepParams.some(
+        (p) =>
+          p.max_matches_per_file !== undefined && p.max_matches_per_file <= 5,
+      );
       expect(
-        hasFrugalLimit,
-        `Expected agent to use a small total_max_matches for a sample usage request. Params used: ${JSON.stringify(
-          grepCalls.map(getGrepParams),
-          null,
-          2,
+        hasMaxMatchesPerFileLimit,
+        `Expected agent to use a small max_matches_per_file (<= 5) for a sample usage request. Actual values: ${JSON.stringify(
+          grepParams.map((p) => p.max_matches_per_file),
         )}`,
       ).toBe(true);
     },
diff --git a/packages/core/src/core/__snapshots__/prompts.test.ts.snap b/packages/core/src/core/__snapshots__/prompts.test.ts.snap
index c827d66ddce..e9445653663 100644
--- a/packages/core/src/core/__snapshots__/prompts.test.ts.snap
+++ b/packages/core/src/core/__snapshots__/prompts.test.ts.snap
@@ -520,7 +520,8 @@ exports[`Core System Prompt (prompts.ts) > should append userMemory with separat
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -650,7 +651,8 @@ exports[`Core System Prompt (prompts.ts) > should handle CodebaseInvestigator wi
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -745,7 +747,8 @@ exports[`Core System Prompt (prompts.ts) > should handle CodebaseInvestigator wi
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -1309,7 +1312,8 @@ exports[`Core System Prompt (prompts.ts) > should include available_skills with
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -1435,7 +1439,8 @@ exports[`Core System Prompt (prompts.ts) > should include correct sandbox instru
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -1552,7 +1557,8 @@ exports[`Core System Prompt (prompts.ts) > should include correct sandbox instru
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -1669,7 +1675,8 @@ exports[`Core System Prompt (prompts.ts) > should include correct sandbox instru
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -1782,7 +1789,8 @@ exports[`Core System Prompt (prompts.ts) > should include planning phase suggest
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -1895,7 +1903,8 @@ exports[`Core System Prompt (prompts.ts) > should include sub-agents in XML for
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -2247,7 +2256,8 @@ exports[`Core System Prompt (prompts.ts) > should return the base prompt when us
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -2360,7 +2370,8 @@ exports[`Core System Prompt (prompts.ts) > should return the base prompt when us
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -2584,7 +2595,8 @@ exports[`Core System Prompt (prompts.ts) > should use chatty system prompt for p
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
@@ -2697,7 +2709,8 @@ exports[`Core System Prompt (prompts.ts) > should use chatty system prompt for p
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your grep_search searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in \`GEMINI.md\` files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.
diff --git a/packages/core/src/prompts/snippets.ts b/packages/core/src/prompts/snippets.ts
index f1b9f6dc127..3dcf346de6e 100644
--- a/packages/core/src/prompts/snippets.ts
+++ b/packages/core/src/prompts/snippets.ts
@@ -165,7 +165,8 @@ export function renderCoreMandates(options?: CoreMandatesOptions): string {
 - **Source Control:** Do not stage or commit changes unless specifically requested by the user.
 
 ## Context Efficiency:
-- Always minimize wasted context window by scoping and limiting all of your ${GREP_TOOL_NAME} searches. e.g.: pass total_max_matches, include, and max_matches_per_file.
+- Always scope and limit your searches to avoid context window exhaustion and ensure high-signal results. Use include to target relevant files and strictly limit results using total_max_matches and max_matches_per_file, especially during the research phase.
+- For broad discovery, use names_only=true or max_matches_per_file=1 to identify files without retrieving their context.
 
 ## Engineering Standards
 - **Contextual Precedence:** Instructions found in ${formattedFilenames} files are foundational mandates. They take absolute precedence over the general workflows and tool defaults described in this system prompt.