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

Annotations already declare readOnlyHint/idempotentHint/openWorldHint=false, so safety is covered. The description adds genuinely new behavioral context: it is free and never billed against a quota, and it is hosted-server-only because the local server has no store. It still omits freshness/rate-limit behavior and any caching semantics.

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?

Purpose is front-loaded, which is good, but the bulk is a single run-on sentence stuffed with parenthetical enumerations that are hard to parse in one pass. Much of the length is output-content listing that only partly earns its place given no output schema.

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?

With no output schema, the description carries the return-value burden and does so fairly thoroughly, naming the moments, their contents, the watch lines, and the signals block. Safety is covered by annotations; the main remaining gap is the absence of any sibling/alternative routing.

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 both parameters are documented there, so baseline is 3. The description reinforces that omitting moment returns all four and implies cursor continues signal pagination, but adds no syntax or format detail beyond the schema.

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 resource (today's read on Robinhood Chain) and enumerates the four 'moments' it aggregates, so an agent can tell it produces a daily digest rather than a single token/lookup. It never explicitly contrasts itself with siblings like keelage_scan or keelage_token, and the jargon ('code passes', 'sized passes') requires the schema's enum descriptions to fully decode.

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?

It gives a partial usage rule ('One moment (moment) or all four' and 'Free, never counted'), and the hosted-server-only note is a real operational constraint. But there is no guidance on when to reach for this digest versus a targeted sibling tool, so selection must be inferred.

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