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

With no annotations provided, the description fully carries the behavioral burden and does so thoroughly. It discloses session-only scope, the $0.001 USDC cost via x402, no API key/account requirement, the 402 response when unpaid, and per-type parsing behavior such as 8-K decoding and Form 4 parsing.

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 dense and front-loads the most important constraint (session-only) before other operational details. Every sentence carries useful information, though it is a single block of text that could benefit from more visual structure.

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 14-parameter tool with no output schema and no annotations, the description covers the most critical operational facts: type-specific required fields, cost, payment behavior, and alternatives. It omits context for body, method, and the expected_* payment parameters, and the response format is only hinted at, so it is not fully complete.

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 description adds critical cross-parameter constraints not present in the schema, such as 'price needs coin plus above, below, or move_pct_24h' and 'edgar needs ticker or cik.' These are essential for valid invocation. However, several parameters (body, method, expected_scheme, expected_network, expected_amount_atomic) remain unexplained in both the schema and the description.

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 clearly states the tool performs a one-time snapshot check of a source, explicitly contrasting it with persistent watch behavior. It enumerates the supported source types and distinguishes itself from create_watch and watch_* siblings by saying 'no watch, no cursor' and 'Use when you will not come back.'

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?

It gives an explicit usage condition ('Use when you will not come back') and a direct alternative ('If the job spans runs, create_watch instead'). It also points to free trial endpoints. However, it does not explicitly explain when to prefer the specialized check_* sibling tools over this generic check_now.

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