historyFetch minified + gzipped bundle size for each of up to 5 specified versions of an npm package and return them side-by-side for size regression tracking.
| Name | Required | Description | Default |
|---|---|---|---|
| package | Yes | ||
| versions | Yes | Comma-sep version list (max 5 to avoid timeouts) |
| Name | Required | Description | Default |
|---|---|---|---|
| history | Yes | Size data for each version | |
| package | Yes | Package name |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly/idempotent/destructive safety. The description adds the limit of 5 versions 'to avoid timeouts' and the 'side-by-side' output format, providing useful behavioral context beyond 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 well-structured sentence, front-loaded with the verb 'Fetch', and every clause adds value. No wasted words.
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?
With an output schema present, return values are covered. The description includes all necessary usage constraints (version limit, purpose) and the read-only/idempotent annotations provide additional context, making the tool fully usable.
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 coverage is 50% with only the 'versions' parameter described. The description compensates by explaining 'up to 5 specified versions' and the comma-separated format. It adds meaning without contradicting schema.
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 'Fetch minified + gzipped bundle size for each of up to 5 specified versions of an npm package' with the specific purpose of 'size regression tracking'. It clearly distinguishes from sibling tools like 'size' by emphasizing multi-version comparison.
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?
The phrase 'for size regression tracking' gives clear context for when to use this tool, implying comparison of multiple versions. However, it does not explicitly name alternatives or exclude cases, so it stops short of a full 5.
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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