StockCake

Resize Image (Outpaint)

resize_image

Change an image's aspect ratio by extending the canvas with AI (GPT Image 2.5) — the subject is kept, new area is generated. Charges credits. Output is the model's native size — about 1.5 megapixels, up to 1536 px on the long edge — whatever the source size; the result reports exact dimensions. For print or larger web use, run upscale_image on the result. Waits up to 45 s, then returns a job_id for get_job. Requires a free StockCake account (the host will prompt to sign in).

Input Schema

TableJSON Schema

Name	Required	Description
`image`	Yes	A StockCake image id (from search_images), one of your own edited image ids (from a previous result), or a job_id. Never a URL.
`prompt`	Yes	What should fill the extended canvas, e.g. 'extend the sandy beach and sky; keep the subject unchanged, do not crop or stretch'
`context`	Yes	In one sentence, what is the user trying to make or find?
`llm_model`	Yes	The exact model identifier you (the assistant) are running as, taken from your system prompt or environment (e.g. "claude-opus-4-8", "gpt-5.2"). Used for analytics only. If you do not know your model identifier with certainty, pass "unknown" — never guess.
`aspect_ratio`	Yes	Target ratio
`conversation_id`	No	Pass the exact conversation_id from the server's previous response, unchanged. The server provides it on the first call — never invent one, and do not issue parallel tool calls until you have it. Keep passing the same conversation_id for the rest of the conversation, including after later user messages or on a different task; do not reset it when the user starts a new request.

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedOct 10, 2026

changedOutput schema / anyOf

Previous value: -[
-  {
-    "additionalProperties": false,
-    "properties": {
-      "credits_charged": {
-        "type": "number"
-      },
-      "image": {
-        "additionalProperties": false,
-        "properties": {
-          "id": {
-            "description": "Edited image id — pass it to download_image or as an image reference",
-            "type": [
-              "number",
-              "null"
-            ]
-          },
-          "url": {
-            "type": "string"
-          }
-        },
-        "required": [
-          "id",
-          "url"
-        ],
-        "type": "object"
-      },
-      "job_id": {
-        "type": "string"
-      },
-      "status": {
-        "const": "completed",
-        "type": "string"
-      }
-    },
-    "required": [
-      "job_id",
-      "status",
-      "image",
-      "credits_charged"
-    ],
-    "type": "object"
-  },
-  {
-    "additionalProperties": false,
-    "properties": {
-      "credits_charged": {
-        "type": "number"
-      },
-      "job_id": {
-        "type": "string"
-      },
-      "message": {
-        "type": "string"
-      },
-      "status": {
-        "const": "pending",
-        "type": "string"
-      }
-    },
-    "required": [
-      "job_id",
-      "status",
-      "credits_charged",
-      "message"
-    ],
-    "type": "object"
-  },
-  {
-    "additionalProperties": {},
-    "properties": {
-      "code": {
-        "type": "string"
-      },
-      "message": {
-        "type": "string"
-      }
-    },
-    "required": [
-      "code",
-      "message"
-    ],
-    "type": "object"
-  }
-]New value: +[
+  {
+    "additionalProperties": false,
+    "properties": {
+      "credits_charged": {
+        "type": "number"
+      },
+      "image": {
+        "additionalProperties": false,
+        "properties": {
+          "dimensions": {
+            "anyOf": [
+              {
+                "additionalProperties": false,
+                "properties": {
+                  "height": {
+                    "type": "number"
+                  },
+                  "width": {
+                    "type": "number"
+                  }
+                },
+                "required": [
+                  "width",
+                  "height"
+                ],
+                "type": "object"
+              },
+              {
+                "type": "null"
+              }
+            ],
+            "description": "Output pixel size; null when the file could not be probed"
+          },
+          "id": {
+            "description": "Edited image id — pass it to get_image (preview), download_image, or as an image reference",
+            "type": [
+              "number",
+              "null"
+            ]
+          },
+          "url": {
+            "type": "string"
+          }
+        },
+        "required": [
+          "id",
+          "url",
+          "dimensions"
+        ],
+        "type": "object"
+      },
+      "job_id": {
+        "type": "string"
+      },
+      "status": {
+        "const": "completed",
+        "type": "string"
+      }
+    },
+    "required": [
+      "job_id",
+      "status",
+      "image",
+      "credits_charged"
+    ],
+    "type": "object"
+  },
+  {
+    "additionalProperties": false,
+    "properties": {
+      "credits_charged": {
+        "type": "number"
+      },
+      "job_id": {
+        "type": "string"
+      },
+      "message": {
+        "type": "string"
+      },
+      "status": {
+        "const": "pending",
+        "type": "string"
+      }
+    },
+    "required": [
+      "job_id",
+      "status",
+      "credits_charged",
+      "message"
+    ],
+    "type": "object"
+  },
+  {
+    "additionalProperties": {},
+    "properties": {
+      "code": {
+        "type": "string"
+      },
+      "message": {
+        "type": "string"
+      }
+    },
+    "required": [
+      "code",
+      "message"
+    ],
+    "type": "object"
+  }
+]

First observedSep 28, 2026

TDQS

A4.5/5.0

Behavior5/5

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

Annotations mark this as a non-read-only, non-idempotent, open-world mutation, and the description adds substantial context beyond them: it charges credits, the output is the model's native ~1.5 MP size regardless of source, it waits up to 45 s before returning a job_id for get_job, and it requires a free StockCake account. This is exactly the async/billing/auth detail annotations cannot convey.

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?

Front-loads the operation and its subject-preservation guarantee, then layers cost, output-size behavior, the async fallback, and auth prerequisites in tight, non-redundant sentences. No sentence is filler.

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

Completeness5/5

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

For a 6-parameter, credit-charging async tool with an output schema, the description covers the essentials an agent must know to call it correctly: cost, expected output resolution, the 45 s wait/job_id path, and the sign-in requirement. Nothing material is missing.

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%, so every parameter (including the non-obvious llm_model and conversation_id conventions) is already documented in the schema. The description adds no parameter-level guidance beyond what the schema provides, so the baseline 3 applies.

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

Purpose5/5

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

States a specific verb and resource ("Change an image's aspect ratio by extending the canvas") and immediately clarifies the mechanism and preservation semantics ("the subject is kept, new area is generated"). It is clearly distinguishable from sibling generate_image (no source image) and upscale_image (which is named for the larger-output case).

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

Usage Guidelines4/5

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

Explicitly routes the agent to a sibling when needed: "For print or larger web use, run upscale_image on the result." It also names the required account and the sign-in prompt. It stops short of stating when NOT to use this tool (e.g. when the user wants a from-scratch image via generate_image), so it is clear context without full exclusion guidance.

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

All StockCake tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?