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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds useful behavioral context beyond that: it discloses that the response is heavy, including the full source of every shipped file, which warns the agent about payload size for a read-only tool.

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?

A single dense sentence with zero waste, front-loading the verb and lookup key before listing return contents. Every clause earns its place by telling the agent what it will receive.

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?

There is no output schema, so the description rightly spends its words on return contents, which it covers well. It could add a note on response size or error behavior for a missing slug, but nothing essential to correct invocation 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?

With one parameter and 100% schema description coverage, the schema already fully documents 'slug'. The description reinforces that lookup is by slug, and the schema ties the value to search_components, so the baseline 3 applies with no additional syntax or format detail needed.

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?

States a specific verb and resource ('Get one component by slug') and enumerates what the response contains: install command, npm dependencies, and full file source. The single-vs-list distinction from search_components is implied by 'one component by slug' but never explicitly contrasted with the sibling tool.

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?

Usage is only implied: the schema's slug description ('Slug from search_components') hints that this follows a search, but the description itself gives no explicit when-to-use, when-not, or alternative routing. An agent can infer the workflow but must open the schema to find it.

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