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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description adds a real behavioral caveat beyond that — patterns recorded on both breakout sides lack an "all" row and are excluded from results. That is exactly the kind of silent omission an agent would otherwise misread as absent data.

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?

Three sentences, front-loaded with what is returned, then a filter summary plus example, then the exclusion rule. Every sentence carries information the agent needs; nothing is padding.

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 10-parameter, zero-required search tool with no output schema, the description conveys the row shape at a high level ("headline result") and the key coverage caveat. It stops short of describing what columns or verdict fields come back, which would help given there is no output 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 100%, so the enum meanings and defaults are already documented in structured fields. The description reinforces that results are pinned to a single market and timeframe but adds no syntax, unit, or interaction 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?

Names a specific verb and resource ("List tested patterns") plus the scope of the returned row ("headline result on one market and timeframe"). It also distinguishes itself from get_pattern_stats by explaining which patterns are omitted here and where to read them.

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?

Gives a concrete use case ("which chart patterns beat chance on forex 4h") that maps directly onto the family/market/timeframe/verdict parameters, and states an explicit carve-out routing the agent to get_pattern_stats. It does not distinguish itself from compare_patterns, which is a remaining gap.

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