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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description goes beyond them by disclosing result cardinality ('up to 5 matches'), result ordering that mirrors the website search, and the meaning of every returned field, including the enum semantics of valuation_status and the banding scheme of upside_band. It does not say what happens on a zero-match query, which keeps it from a 5.

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 and usage are front-loaded in the first two clauses; the remaining length is a field glossary that is justified because no output schema exists. No filler sentences.

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 full burden of explaining returns, and it does so thoroughly (symbol, name, valuation status, bands, quality, evidence, deep link). Missing only edge-case behavior such as zero or ambiguous multi-match results.

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 100%, so the baseline is 3, but the description adds that the query accepts not just a name or ticker (as the schema says) but also 'ISIN-like input', and frames the input as resolving to an exact TICKER.EXCHANGE listing.

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 (find/resolve), resource (listed company), input modes (name, ticker, ISIN-like), and the exact scope (up to 5 matches from the 35,000+ covered universe). It is clearly distinguishable from siblings like get_stock_preview and get_stock_verdict, which consume the symbol this tool produces.

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?

Explicitly says when to reach for it: 'when the user names a company or the exchange is unclear', and explains the downstream value ('symbol to pass to the other tools'). It stops short of naming alternatives or stating when not to use it (e.g. when a symbol is already known), so it is clear context without full routing.

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