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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds useful context beyond annotations: the exhaustive 'every' scope, the specific site, and the returned metadata fields. Minor gaps such as pagination or ordering are not significant for this low-risk read 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?

Two sentences with no redundant words. The first sentence front-loads the action, scope, and output fields; the second provides routing guidance. Every sentence 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?

Given the tool's low complexity (one optional parameter, output schema present, read-only annotations), the description is sufficient for an agent to select and invoke it correctly. It also distinguishes itself from the relevant sibling tool.

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?

The input schema already fully describes the single optional `locale` parameter with an enum and a clear description ('Restrict by language'). Schema description coverage is 100%, so the description does not need to add much; it introduces language as an output field but not the parameter semantics, which is acceptable.

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 a specific verb ('List'), a precise resource ('every long-form essay published on articles.santismm.com'), and the returned fields (language, dates, topics, canonical URLs). It clearly differentiates from search_articles and other sibling list tools.

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 description explicitly says when to use this tool ('Use this to browse the essay catalogue') and when to use an alternative ('use search_articles when you have a topic rather than a slug'). This gives an agent unambiguous routing guidance.

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