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

With no annotations, the description carries the full burden and does so well: it discloses the data source (end-of-day, not live), the result ordering (stocks where the rule just turned true first, then by volume vs 20-day average), and the default result cap. It does not say what happens on an invalid rule or what fields each returned stock carries.

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?

The purpose leads, then two labeled lines map cleanly onto the two parameters, then a single caveat about EOD data. No filler sentences; every line adds information an agent would otherwise have to guess.

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 two-parameter tool with no annotations and no output schema, the description establishes inputs, universe, ordering, and data freshness but never describes the shape of a returned stock record or error behavior. That leaves a real gap since no output schema exists to fill it.

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 coverage is 0%, so the description must define both parameters, and it does: rule is a formula in Trade Manager's language with a concrete worked example, and limit is the max stocks returned with a stated default and ranking semantics. It omits where to find the rule language reference (the rule_language sibling), leaving a minor gap.

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 plus scope: 'List the S&P 500 stocks that match a setup at the latest daily close,' with parenthetical example. The universe, timeframe, and output are unambiguous. It does not explicitly separate itself from siblings like test_setup or what_happened_today, so it stops short of a 5.

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 parenthetical example ('what broke out today on volume') and the note that it 'Uses end-of-day data, not live prices' imply when to reach for it and rule out live/intraday use. However, no sibling alternative is named - an agent cannot tell from this text whether to use scan_today or test_setup for a given question.

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