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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so the safety profile is covered. The description adds meaningful substance beyond that: each metric carries latest annual, prior annual, YoY %, latest reported period, plus derived margins and debt-to-equity, all in USD 'as reported' — details an agent would otherwise have to discover by calling.

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?

Two dense sentences, front-loaded with the source and scope before the metric inventory. The metric list is long but every item earns its place by telling the agent whether a needed figure is retrievable without a follow-up call.

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 burden of explaining returns and does so thoroughly — metrics, comparison periods, derived ratios, currency. The only missing piece is failure behavior for unresolvable tickers/CIKs and whether all metrics are always present.

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%, with ticker_or_cik documented including examples for both ticker and CIK forms. The description says nothing additional about the parameter (e.g. whether an ambiguous ticker fails or resolves), so it matches the baseline where the schema does the work.

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 resource (10-K/10-Q XBRL financials) and enumerates exactly which metrics are returned, so the agent knows what it gets. It doesn't differentiate itself from the sibling get_company_concept, which also returns XBRL financial data, leaving the agent to infer that this is a bundled summary rather than a single-concept timeseries.

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?

No explicit when-to-use or when-not-to-use guidance and no sibling is named, but the word 'snapshot' plus the 'latest annual value, prior annual value, YoY growth' framing implies a one-shot summary in contrast to a per-concept time series. That implication is the only routing signal available.

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