base64_encodeBase64 encode.
| Name | Required | Description | Default |
|---|---|---|---|
| s | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| body | Yes | Base64 encoded string | |
| status | Yes | HTTP status code | |
| content_type | Yes | Content-Type header |
Changes observed during successful MCP inspections.
Input schema / examplesAdded value: +[
+ {
+ "s": "hello world"
+ },
+ {
+ "s": "sensitive data"
+ }
+]Output schema / (root)Previous value: -nullNew value: +{
+ "properties": {
+ "body": {
+ "description": "Base64 encoded string",
+ "type": "string"
+ },
+ "content_type": {
+ "description": "Content-Type header",
+ "type": "string"
+ },
+ "status": {
+ "description": "HTTP status code",
+ "type": "number"
+ }
+ },
+ "required": [
+ "status",
+ "content_type",
+ "body"
+ ],
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already indicate readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the description adds little behavioral context. It does not contradict annotations, but also does not disclose any additional traits (e.g., output format or limitations).
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single short sentence, which is concise. However, it sacrifices clarity for brevity, leaving out important details. It could be slightly longer without becoming verbose.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given the tool's simplicity and the presence of an output schema, the description is nearly complete but fails to explain the input parameter. For a trivial encoding tool, this is acceptable but not exemplary.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%. The parameter 's' is left undocumented in the description. While the name and type suggest it is the input string, the description should explicitly state its role and any constraints.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description 'Base64 encode.' clearly states the verb (encode) and resource (Base64), but it is extremely terse. It is not misleading and distinguishes from the sibling base64_decode, but lacks any additional context about what the tool does exactly.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidelines are provided on when to use this tool versus alternatives like base64_decode. The description gives no context about appropriate use cases or prerequisites.
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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