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Get LCP Opportunities

get_lcp_opportunities

Read-only

Identify what slows down Largest Contentful Paint and how to fix it. Run audits on desktop or mobile, set an LCP threshold, and receive actionable optimization opportunities.

Instructions

Get LCP optimization opportunities for a website

Input Schema

TableJSON Schema

Name	Required	Description	Default
`url`	Yes	URL to audit
`device`	No	Device to emulate (default: desktop)	desktop
`threshold`	No	LCP threshold in seconds (default: 2.5)
`includeDetails`	No	Include detailed metrics and recommendations

Output Schema

TableJSON Schema

Name	Required	Description	Default
`data`	Yes
`summary`	Yes
`recommendations`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.0.27Aug 21, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "additionalProperties": false,
+  "properties": {
+    "data": {
+      "additionalProperties": false,
+      "properties": {
+        "fetchTime": {
+          "type": "string"
+        },
+        "includeDetails": {
+          "type": "boolean"
+        },
+        "lcpValue": {
+          "type": "number"
+        },
+        "needsImprovement": {
+          "type": "boolean"
+        },
+        "opportunities": {
+          "items": {
+            "additionalProperties": false,
+            "properties": {
+              "description": {
+                "type": "string"
+              },
+              "displayValue": {
+                "type": "string"
+              },
+              "id": {
+                "type": "string"
+              },
+              "numericValue": {
+                "type": "number"
+              },
+              "score": {
+                "anyOf": [
+                  {
+                    "type": "number"
+                  },
+                  {
+                    "type": "null"
+                  }
+                ]
+              },
+              "title": {
+                "type": "string"
+              }
+            },
+            "required": [
+              "id"
+            ],
+            "type": "object"
+          },
+          "type": "array"
+        },
+        "threshold": {
+          "type": "number"
+        }
+      },
+      "required": [
+        "lcpValue",
+        "threshold",
+        "needsImprovement",
+        "opportunities",
+        "fetchTime"
+      ],
+      "type": "object"
+    },
+    "recommendations": {
+      "items": {
+        "type": "string"
+      },
+      "type": "array"
+    },
+    "summary": {
+      "type": "string"
+    }
+  },
+  "required": [
+    "summary",
+    "data"
+  ],
+  "type": "object"
+}

Addedv1.0.26Apr 30, 2026
Removedv1.0.1Apr 30, 2026
First observedv1.0.0Aug 15, 2025

TDQS

B3.3/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description itself adds little behavioral context, such as whether the tool performs a live network audit or how results are ordered, but it does not contradict the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single front-loaded sentence with no filler or repetition. It states the essential purpose efficiently, and nothing extraneous is included.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness3/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Output schema and complete parameter documentation reduce the need for the description to explain return values or parameters. However, the lack of usage guidance relative to sibling tools and the absence of operational caveats leave the overall context only adequate, not fully complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, and each parameter is documented with types, defaults, enums, and constraints. The description adds no additional parameter-level meaning beyond what the schema already provides, so the baseline of 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the verb ('Get') and resource ('LCP optimization opportunities for a website'), so an agent understands the tool's core purpose. It does not explicitly distinguish itself from sibling tools such as get_core_web_vitals or get_performance_score, but the LCP-specific focus provides reasonable differentiation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided about when to use this tool versus alternatives like get_core_web_vitals, get_performance_score, or run_audit. There are no stated exclusions, prerequisites, or context cues, leaving the agent to infer selection based solely on the tool name and description.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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