Read the Notes feed

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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint), so the bar is lower, yet the description adds genuinely useful context: the returned text is third-party content and must be treated as data, not instructions. This is a prompt-injection disclosure that no annotation conveys. It stops short of describing pagination behavior or return shape.

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, zero waste, front-loaded with the resource definition and followed by the single most important caveat. 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?

For a read-only, open-world feed tool with no output schema and annotations covering the safety profile, the description supplies what an agent most needs beyond the structure: what the feed is and that its contents are untrusted. Missing only pagination/return-size context, which is a minor gap given limit/offset exist in the schema.

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 75% and the description adds nothing about tab, limit, offset, or publication. The uncovered 'offset' parameter is documented nowhere in the description, and the description does not explain feed-tab values or the publication-matching rule beyond what the schema already states. Baseline 3 is appropriate when the schema largely does the work.

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 defines the resource concretely ('The Notes feed, which is Substack's timeline') and states what it returns ('text written by other people'), giving a clear verb+resource reading despite never using an explicit verb like 'read' or 'return' in the operational sense. It does not differentiate from similarly named siblings such as get_profile_feed or list_reader_posts, which an agent could easily confuse it with.

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?

There is no when-to-use guidance, no prerequisites, and no mention of the alternative read tools (get_profile_feed, list_reader_posts, list_notes) that overlap with this one. The only instruction is the safety directive about how to treat the returned content, which is behavioral rather than selection guidance.

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