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

With no annotations provided, the description carries the full behavioral burden and does well: it discloses pricing, the daily free allowance, the 402 payment flow, exact retry semantics with payment_tx, and bearer-token bypass. It does not cover data freshness, full rate-limit behavior, or permission requirements beyond auth/payment.

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 description is front-loaded with purpose and filters, then cleanly separates payment instructions. Every sentence, including the payment and auth details, earns its place for a paid tool.

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 six-parameter optional-filter tool with a full input schema and an output schema, the description covers purpose, ranking behavior, payment, and auth adequately. It could further define the tracked universe or no-filter default behavior, but an agent has enough information to invoke it correctly.

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 all six parameters are already documented in the schema. The description adds useful context around payment_tx and the daily free allowance, but it does not add meaning beyond the schema for screening parameters such as max_pe, min_dividend, min_market_cap, or agent_id.

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: screen the tracked large-cap universe by market cap, P/E, dividend yield, and sector, returning stocks ranked by market cap. It clearly distinguishes this raw market-data screen from a fundamentals-driven screen, but it does not explicitly differentiate itself from listed siblings like quote, price_history, or sector_performance.

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 description gives a clear use context: a raw market-data filter, with financial-signals-mcp's composite_value_score offered as the alternative for ranked fundamentals-driven screening. It does not explicitly state when to avoid this tool or how it relates to sibling tools such as sector_performance, so it stops short of full when/when-not guidance.

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