TinyFn

subtract_time_2

Subtract time from a datetime.

Input Schema

Name	Required	Description
`days`	No	Days to subtract
`hours`	No	Hours to subtract
`minutes`	No	Minutes to subtract
`seconds`	No	Seconds to subtract
`datetime_str`	Yes	Datetime in ISO format

Output Schema

Name	Required	Description	Default
`error`	No
`result`	No
`original`	No
`subtracted`	No

Schema Changelog

Changes observed during successful MCP inspections.

Changed3 schema fields changedOct 23, 2026

addedOutput schema / $defs / SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

removedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"app__routers__time_utils__SubtractTimeResponse"New value: +"SubtractTimeResponse"

Changed3 schema fields changedAug 29, 2026

removedOutput schema / $defs / SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

addedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"SubtractTimeResponse"New value: +"app__routers__time_utils__SubtractTimeResponse"

Changed3 schema fields changedAug 29, 2026

addedOutput schema / $defs / SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

removedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"app__routers__time_utils__SubtractTimeResponse"New value: +"SubtractTimeResponse"

Changed3 schema fields changedJul 27, 2026

removedOutput schema / $defs / SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

addedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"SubtractTimeResponse"New value: +"app__routers__time_utils__SubtractTimeResponse"

Changed3 schema fields changedJul 17, 2026

addedOutput schema / $defs / SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

removedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"app__routers__time_utils__SubtractTimeResponse"New value: +"SubtractTimeResponse"

Changed3 schema fields changedJul 13, 2026

removedOutput schema / $defs / SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

addedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"SubtractTimeResponse"New value: +"app__routers__time_utils__SubtractTimeResponse"

Changed3 schema fields changedJul 8, 2026

addedOutput schema / $defs / SubtractTimeResponse

Added value: +{
+  "properties": {
+    "error": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Error"
+    },
+    "original": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Original"
+    },
+    "result": {
+      "anyOf": [
+        {
+          "type": "string"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "title": "Result"
+    },
+    "subtracted": {
+      "anyOf": [
+        {
+          "$ref": "#/$defs/TimeAddedParts"
+        },
+        {
+          "type": "null"
+        }
+      ]
+    }
+  },
+  "title": "SubtractTimeResponse",
+  "type": "object"
+}

removedOutput schema / $defs / app__routers__time_utils__SubtractTimeResponse

Removed value: -{
-  "properties": {
-    "error": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Error"
-    },
-    "original": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Original"
-    },
-    "result": {
-      "anyOf": [
-        {
-          "type": "string"
-        },
-        {
-          "type": "null"
-        }
-      ],
-      "title": "Result"
-    },
-    "subtracted": {
-      "anyOf": [
-        {
-          "$ref": "#/$defs/TimeAddedParts"
-        },
-        {
-          "type": "null"
-        }
-      ]
-    }
-  },
-  "title": "SubtractTimeResponse",
-  "type": "object"
-}

changedOutput schema / x-fastmcp-top-level-schema

Previous value: -"app__routers__time_utils__SubtractTimeResponse"New value: +"SubtractTimeResponse"

First observedJun 27, 2026

TDQS

C2.8/5.0

Behavior2/5

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

No annotations provided, so description carries full burden. It only states the basic action, omitting behavioral details such as handling invalid input, timezone considerations, or output format.

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

Conciseness3/5

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

Extremely concise (4 words) but overly minimal for a tool with 5 parameters. Could benefit from a brief expansion on what time units are supported.

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

Completeness2/5

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

Given the presence of sibling tools and 5 parameters, the description lacks essential context such as return type, format specifics, and differentiation. Output schema is present but description doesn't leverage it.

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 coverage is 100% and each parameter is described, so baseline applies. Description adds no additional meaning beyond the schema.

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?

Description clearly states the verb and resource: subtract time from a datetime. However, it does not differentiate from the sibling tool 'subtract_time', which likely has similar purpose.

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 on when to use this tool versus alternatives like 'subtract_time'. No context on prerequisites or exclusions.

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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subtract_time_2

Input Schema

Output Schema

Schema Changelog

TDQS

Glama MCP Gateway

Resources