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

Annotations already declare readOnlyHint=true and destructiveHint=false and openWorldHint=true, so safety is covered. The description adds real value beyond that: the formula for member read ratio, the rule that earnings appear only for paywalled stories, and the auth requirement (Cotlet API key with access to this app).

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?

Front-loads the metric list, then adds two genuinely useful clarifications (ratio definition, paywall-conditional earnings) and the auth note. No filler sentences, though the phrasing is slightly dense and could be tightened.

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 read-only stats tool with no output schema, the description covers what is returned, how one metric is computed, the conditionality of earnings, and the auth requirement. The safety profile is carried by annotations, so nothing critical is missing; the only gap is not distinguishing it from the other Medium stats endpoints.

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 story_id parameter is documented as coming from list_stories. The description adds no syntax or format detail for the parameter, so the baseline of 3 applies since the schema carries the burden.

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 story stats') and enumerates exactly which metrics are returned (views, reads, member read ratio, claps, responses, earnings). This distinguishes it from medium_get_story and medium_get_account_stats by scope, though it never names those siblings explicitly.

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 implied (fetch the detailed stats page for a story) and it notes the paywall condition for earnings, but there is no explicit when-to-use guidance or routing to the alternative stats tools (medium_get_account_stats for account-level figures, medium_get_story for story content).

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