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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false), so the bar is lower. With no output schema, the description adds real value by enumerating the payload: headline description, key figures, context, FAQ, PDF and open-dataset links. It does not describe behavior for a missing/invalid slug.

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 front-loaded sentence that identifies the resource, the key, and the return contents with zero filler. Every clause earns its place.

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?

Because no output schema exists, the description compensates by listing what the issue contains, which is enough for an agent to judge relevance. Minor gaps remain around invalid-slug behavior, but for a 1-parameter read tool this is close to complete.

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 100% and the single slug parameter already carries the format example, so the description's slug example is largely redundant. The only added meaning is pointing to get_index_summary as the source of valid slug values, which is closer to usage guidance than parameter semantics.

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 (get) and resource (one published GX Index monthly issue) plus the retrieval key (slug). It explicitly distinguishes itself from the sibling get_index_summary, which lists issues rather than returning one.

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?

Names get_index_summary as the way to discover valid slugs, which implicitly tells the agent when to use that tool instead of this one. There is no explicit exclusion or failure-handling guidance (e.g. what happens with an unknown slug), so it stops short of a 5.

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