OnlineCyberTools MCP (280+ filterable tools)

crypto_password_generator_passphrase

Read-only

Generate memorable diceware passphrases by joining random words from curated lists. Customize word count, separators, capitalization, numbers, and symbols for secure, human-typable passwords.

Instructions

Diceware Passphrase Generator. Generate one or more memorable diceware-style passphrases by joining randomly-chosen dictionary words with a separator. Use this for human-typable word passphrases; use crypto_password_generator for dense mixed-character passwords or crypto_password_generator_pin for numeric-only codes. Words are picked with crypto.getRandomValues. Runs locally on the input you provide: read-only, non-destructive, contacts no external service, and is rate-limited (30 requests/min, 200/hour, 1000/day for anonymous callers). Returns each passphrase with its component words, character length, and word count, plus the normalized options actually applied.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`wordCount`	No	Number of words per passphrase. Clamped to 3-10.
`separator`	No	String placed between words. Any string is allowed; pass an empty string to concatenate words with no separator.	-
`capitalize`	No	When true, the first letter of each word is uppercased.
`includeNumbers`	No	When true, a random number (10-9999) is appended to the end of the passphrase.
`includeSymbols`	No	When true, one random symbol from !@#$%&* is appended to the end of the passphrase.
`wordList`	No	Source word list. "common" is 64 five-to-six-letter words; "simple" is 40 short three-to-four-letter words. An unknown value falls back to "common".	common
`quantity`	No	How many passphrases to generate. Clamped to 1-50.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`passphrases`	No	The generated passphrases, one entry per requested quantity.
`options`	No	The normalized options actually used after clamping defaults.

Schema Changelog

Changes observed during successful MCP inspections.

Changed19 schema fields changedv0.5.1Jun 3, 2026

addedInput schema / additionalProperties
```
Added value: +false
```

addedInput schema / properties / capitalize

Added value: +{
+  "default": false,
+  "description": "When true, the first letter of each word is uppercased.",
+  "type": "boolean"
+}

removedInput schema / properties / excludeSimilar
```
Removed value: -{
-  "type": "boolean"
-}
```
removedInput schema / properties / includeLowercase
```
Removed value: -{
-  "type": "boolean"
-}
```
addedInput schema / properties / includeNumbers / default
```
Added value: +false
```

addedInput schema / properties / includeNumbers / description

Added value: +"When true, a random number (10-9999) is appended to the end of the passphrase."

addedInput schema / properties / includeSymbols / default
```
Added value: +false
```

addedInput schema / properties / includeSymbols / description

Added value: +"When true, one random symbol from !@#$%&* is appended to the end of the passphrase."

removedInput schema / properties / includeUppercase
```
Removed value: -{
-  "type": "boolean"
-}
```

removedInput schema / properties / length

Removed value: -{
-  "type": "integer"
-}

addedInput schema / properties / quantity / default
```
Added value: +1
```

addedInput schema / properties / quantity / description

Added value: +"How many passphrases to generate. Clamped to 1-50."

addedInput schema / properties / quantity / maximum
```
Added value: +50
```
addedInput schema / properties / quantity / minimum
```
Added value: +1
```

addedInput schema / properties / separator

Added value: +{
+  "default": "-",
+  "description": "String placed between words. Any string is allowed; pass an empty string to concatenate words with no separator.",
+  "type": "string"
+}

addedInput schema / properties / wordCount

Added value: +{
+  "default": 4,
+  "description": "Number of words per passphrase. Clamped to 3-10.",
+  "maximum": 10,
+  "minimum": 3,
+  "type": "integer"
+}

addedInput schema / properties / wordList

Added value: +{
+  "default": "common",
+  "description": "Source word list. \"common\" is 64 five-to-six-letter words; \"simple\" is 40 short three-to-four-letter words. An unknown value falls back to \"common\".",
+  "enum": [
+    "common",
+    "simple"
+  ],
+  "type": "string"
+}

changedInput schema / required

Previous value: -[
-  "length",
-  "includeUppercase",
-  "includeLowercase",
-  "includeNumbers",
-  "includeSymbols",
-  "excludeSimilar",
-  "quantity"
-]New value: +[]

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "properties": {
+    "options": {
+      "description": "The normalized options actually used after clamping defaults.",
+      "properties": {
+        "capitalize": {
+          "description": "Whether each word was capitalized.",
+          "type": "boolean"
+        },
+        "includeNumbers": {
+          "description": "Whether a trailing number was appended.",
+          "type": "boolean"
+        },
+        "includeSymbols": {
+          "description": "Whether a trailing symbol was appended.",
+          "type": "boolean"
+        },
+        "quantity": {
+          "description": "Number of passphrases generated.",
+          "type": "integer"
+        },
+        "separator": {
+          "description": "Separator string applied between words.",
+          "type": "string"
+        },
+        "wordCount": {
+          "description": "Effective word count applied.",
+          "type": "integer"
+        },
+        "wordList": {
+          "description": "Word list source actually used.",
+          "type": "string"
+        }
+      },
+      "type": "object"
+    },
+    "passphrases": {
+      "description": "The generated passphrases, one entry per requested quantity.",
+      "items": {
+        "properties": {
+          "length": {
+            "description": "Character length of the full passphrase string.",
+            "type": "integer"
+          },
+          "passphrase": {
+            "description": "The full passphrase string, including any appended number or symbol.",
+            "type": "string"
+          },
+          "wordCount": {
+            "description": "Number of words used in this passphrase.",
+            "type": "integer"
+          },
+          "words": {
+            "description": "The component words chosen for this passphrase, in order.",
+            "items": {
+              "type": "string"
+            },
+            "type": "array"
+          }
+        },
+        "type": "object"
+      },
+      "type": "array"
+    }
+  },
+  "type": "object"
+}

First observedv0.1.0May 31, 2026

TDQS

A4.7/5.0

Behavior5/5

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

Annotations show readOnlyHint=true and destructiveHint=false. The description adds key transparency details: local execution, crypto.getRandomValues, rate limits (30/min, 200/hr, 1000/day), and non-destructive nature. No contradiction.

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 5 sentences, well-organized, front-loading the purpose and usage, with no redundant or unnecessary information.

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?

Given the tool's complexity (7 parameters, optional output schema), the description covers purpose, usage, behavioral details, and links to alternatives. The mention of return structure complements the output schema, making it complete for effective agent selection.

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% with good parameter descriptions; the tool description does not add additional semantic meaning beyond what the schema already provides, though it does reference the output structure.

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?

The description clearly states the purpose as generating diceware-style passphrases, specifies the verb 'generate', and distinguishes from sibling tools (crypto_password_generator, crypto_password_generator_pin) by noting their different use cases (dense passwords, numeric codes).

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

Usage Guidelines5/5

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

Explicitly states when to use this tool ('for human-typable word passphrases') and when to use alternatives ('use crypto_password_generator for dense mixed-character passwords or crypto_password_generator_pin for numeric-only codes'), providing clear guidance.

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

Deploy Server