Skip to main content
Glama

Tanod

by dev.tanod
OverviewDiscussionsAdmin

utilpeek: make a 1-D barcode image (SVG or PNG)

make_barcode
Idempotent

utilpeek: make a 1-D barcode image. For QR codes use make_qr_code; to find the product behind a number use lookup_barcode_product. Returns svg (text, with width_mm/height_mm) or data_base64 (PNG, with width_px/height_px; output "url": a 24 h link), plus encoded and bytes. A supplied check digit (ean13, ean8, upca, isbn13) must be right: a wrong one is a 422 invalid_checksum (not charged) rather than silently encoding a different number. Every output is decoded again with an independent reader (ZXing-C++): the answer carries verified: true and decoded_text, and a symbol that does not decode to the requested value is a 500 verify_failed (not charged). Encoded locally; typically under 0.1 s. Price: USD 0.001. Free: 10 utilpeek calls per IP per UTC day. Docs: https://tanod.dev/learn/barcode-generator-api.html

Input Schema

NameRequiredDescriptionDefault
dataYesValue to encode (see the type rules).
textNoPrint the human-readable line (default true).
typeNoSymbology (default code128).code128
formatNosvg (text) or png (base64).svg
outputNobase64 (default): the file comes back inline as base64. url: the file is stored for 24 hours and the reply carries a download link (url, expires_at, bytes, content_type, sha256) instead of the base64, which keeps the file out of your context window.base64

Output Schema

NameRequiredDescriptionDefault
svgNo
textNo
typeNo
bytesNo
errorNoOnly on an error result: an object {code, message}, or the reason string of an x402 PaymentRequired object.
formatNo
sourceNo
encodedNo
verifiedNo
width_mmNo
width_pxNo
height_mmNo
height_pxNo
data_base64No
verified_byNo
verify_noteNo
content_typeNo
decoded_textNo

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed4 schema fields changed
    • addedOutput schema / properties / decoded_text
      Added value: +{
+  "type": [
+    "string",
+    "null"
+  ]
+}
    • addedOutput schema / properties / verified
      Added value: +{
+  "type": [
+    "boolean",
+    "null"
+  ]
+}
    • addedOutput schema / properties / verified_by
      Added value: +{
+  "properties": {
+    "library": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "license": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "url": {
+      "type": [
+        "string",
+        "null"
+      ]
+    }
+  },
+  "type": [
+    "object",
+    "null"
+  ]
+}
    • addedOutput schema / properties / verify_note
      Added value: +{
+  "type": [
+    "string",
+    "null"
+  ]
+}
  2. Changed1 schema field changed
    • addedInput schema / properties / output
      Added value: +{
+  "default": "base64",
+  "description": "base64 (default): the file comes back inline as base64. url: the file is stored for 24 hours and the reply carries a download link (url, expires_at, bytes, content_type, sha256) instead of the base64, which keeps the file out of your context window.",
+  "enum": [
+    "base64",
+    "url"
+  ],
+  "title": "Output",
+  "type": "string"
+}
  3. Changed1 schema field changed
    • changedOutput schema / (root)
      Previous value: -nullNew value: +{
+  "properties": {
+    "bytes": {
+      "type": [
+        "integer",
+        "null"
+      ]
+    },
+    "content_type": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "data_base64": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "encoded": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "error": {
+      "description": "Only on an error result: an object {code, message}, or the reason string of an x402 PaymentRequired object."
+    },
+    "format": {
+      "enum": [
+        "svg",
+        "png",
+        null
+      ],
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "height_mm": {
+      "type": [
+        "number",
+        "null"
+      ]
+    },
+    "height_px": {
+      "type": [
+        "integer",
+        "null"
+      ]
+    },
+    "source": {
+      "properties": {
+        "library": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "license": {
+          "type": [
+            "string",
+            "null"
+          ]
+        },
+        "url": {
+          "type": [
+            "string",
+            "null"
+          ]
+        }
+      },
+      "type": [
+        "object",
+        "null"
+      ]
+    },
+    "svg": {
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "text": {
+      "type": [
+        "boolean",
+        "null"
+      ]
+    },
+    "type": {
+      "enum": [
+        "code128",
+        "ean13",
+        "ean8",
+        "upca",
+        "isbn13",
+        "code39",
+        null
+      ],
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "width_mm": {
+      "type": [
+        "number",
+        "null"
+      ]
+    },
+    "width_px": {
+      "type": [
+        "integer",
+        "null"
+      ]
+    }
+  },
+  "type": "object"
+}
  4. Added

TDQS

A4.8/5.0
Behavior5/5

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

Adds substantial behavior beyond the annotations: check-digit validation with a 422 invalid_checksum that is not charged, independent re-decode via ZXing-C++ yielding verified/decoded_text with a 500 verify_failed that is not charged, local encoding with sub-0.1s latency, USD 0.001 pricing, and a 10-call/IP/UTC-day free tier. No contradiction with readOnlyHint=false or idempotentHint=true.

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

Conciseness4/5

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

Front-loaded with the routing sentence, then failure modes, then return shapes, then cost — a sensible ordering. It is dense and slightly long for the operation, with verification and pricing detail arguably more than an agent needs to select the tool, but nearly every clause is non-redundant.

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 5-param, multi-format generation tool with three enum parameters, the description covers routing, valid input constraints, error semantics, output representations, latency, and cost. An output schema exists, yet the description's brief return-shape sketch adds useful orientation without over-specifying.

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

Parameters4/5

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

Schema description coverage is already 100%, so the baseline is 3. The description goes further by tying semantics to parameters: the check-digit rule constrains valid `data` per `type`, and it spells out the return shape of the `format`/`output` choice (svg with width_mm/height_mm vs data_base64 with width_px/height_px, or a 24h url link). It does not explain `text` (human-readable line), a minor gap.

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+resource ('make a 1-D barcode image') and immediately disambiguates from the two nearest siblings, make_qr_code and lookup_barcode_product. An agent can tell exactly what this does and does not cover without opening the schema.

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 routes: 'For QR codes use make_qr_code; to find the product behind a number use lookup_barcode_product.' It also gives the condition that triggers the two failure paths (wrong check digit for ean13/ean8/upca/isbn13) and the cost/free-tier constraints that affect whether to call it.

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

All Tanod toolsInspect
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