versionsEvery published version of a deno.land/x module, newest first, plus which one is latest. Keyless.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| latest | No | Latest version identifier | |
| versions | No | List of available versions |
Changes observed during successful MCP inspections.
Input schema / examplesAdded value: +[
+ {
+ "name": "std"
+ }
+]Output schema / (root)Previous value: -nullNew value: +{
+ "properties": {
+ "latest": {
+ "description": "Latest version identifier",
+ "type": "string"
+ },
+ "versions": {
+ "description": "List of available versions",
+ "items": {
+ "type": "string"
+ },
+ "type": "array"
+ }
+ },
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds meaningful context beyond annotations: it returns all published versions, orders them newest first, flags the latest version, and requires no key (keyless). These are behavioral details not encoded in the annotations.
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 sentence with no filler, front-loading the core behavior and ending with the keyless detail. Every phrase adds value and the structure is immediately scannable.
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?
For a one-parameter, read-only listing tool with an output schema and rich annotations, the description covers purpose, input semantics, ordering, and the latest flag. Nothing essential for invoking the tool correctly is missing.
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?
The schema provides no description for the `name` parameter (0% coverage). The description compensates by indicating the resource is a deno.land/x module, making it clear that `name` is the module name. This is sufficient for correct invocation, though format constraints are not detailed.
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 states the tool lists every published version of a deno.land/x module, newest first, and identifies which is `latest`. This clearly distinguishes it from the singular `version` sibling by covering the full version set and the latest marker.
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?
It provides clear context: use this when you need the complete version list and the latest version. It does not explicitly name alternatives or exclusions, but the intended use case is unambiguous from the description.
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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