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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely useful framing (incremental typeahead, which venues are searched, EXCHANGE:SYMBOL result shape) but omits matching semantics such as prefix vs. substring and empty-query behavior.

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?

A single tight sentence that front-loads the core purpose and then scopes the exchange coverage and return format. No filler or redundancy.

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?

An output schema exists, so return-value documentation is unnecessary, and annotations cover the safety profile. What remains missing is the typeahead matching contract (what an empty or no-match query yields), which matters for correct invocation of a search-style 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 single 'query' parameter has 0% schema description, so the description must carry the weight. 'Typeahead search' implies the query is the partial string to match, but it adds no detail on format, minimum length, or how the empty default is handled. Partial compensation for the coverage 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?

The description gives a specific verb (typeahead search) and resource (tickers / @-mention symbols), plus the exact output format (EXCHANGE:SYMBOL) and covered exchanges (NASDAQ, NYSE, BIST, Binance). That clearly separates it from the surrounding analysis/scanner siblings. It stops short of 5 only because it does not name any sibling it might be confused 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?

Usage is implied by 'Typeahead search for @-mentions', suggesting it is meant to resolve a partial symbol as a user types. There is no explicit when-to-use vs. alternative, and no stated preconditions or exclusions. Adequate but relies on inference.

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