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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is fully covered structurally. The description's only added behavioral signal is 'full record', hinting the response is the complete entity rather than a summary, which is modest but genuine value.

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?

One sentence, front-loaded with the verb and resource, with zero filler. Nothing could be removed without losing meaning.

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 single-parameter read lookup with a full output schema and rich annotations, the description covers the essentials; return values and safety are handled elsewhere. Minor gaps around slug-not-found behavior and repo-vs-plugin disambiguation keep it off a 5.

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 100% and the single parameter already carries a concrete example ('safishamsi-graphify'), so the schema does the heavy lifting. The description adds no format, case-sensitivity, or namespace nuance beyond what the schema provides.

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?

Specific verb ('Fetch') plus resource ('full record for one repo/plugin'), and 'one' signals single-item retrieval as opposed to the list_repos sibling. It stops short of naming a sibling or fully disambiguating repo vs plugin as a lookup key, but an agent can tell what it does at a glance.

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?

'by slug' implies the precondition (you must already have a slug), which is a reasonable usage cue. However, there is no explicit when-to-use-this-vs-list_repos-or-get_tool guidance and no statement of what happens when the slug is unknown.

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