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

With no annotations provided, the description must carry the full behavioral burden. It implies a read-only operation ('Today's free levels') and describes the return content, which is transparent. However, it does not explicitly state there are no side effects, nor does it mention authentication, rate limits, or any limitations on the input symbol. It adds some behavioral context but leaves gaps.

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 two concise sentences: the first states the core purpose and return content, the second adds a usage restriction. No wasted words; the most important information is front-loaded. It is highly efficient and well-structured.

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 simple tool with one parameter and no output schema, the description covers the essential context: what data is returned, the scope (single instrument), and the usage restriction. It does not address error conditions or authentication, but for this tool's simplicity the coverage is reasonably complete. A missing note on validity of symbols or response format could be a minor gap, but overall it is adequate.

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 0%, so the description must compensate. It provides examples ('NQ', 'ES') and clarifies that the symbol is an instrument, adding meaning beyond the bare 'symbol' string. However, it does not specify valid symbol formats, whether the symbol is case-sensitive, or how errors are handled for invalid inputs. It partially compensates but is not exhaustive.

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 opens with a specific verb and resource — 'Today's free levels for one instrument' — and enumerates exactly what is returned (market regime, named free levels with prices, desk read excerpt, and count of further levels). It clearly distinguishes itself from siblings like get_paths (paths) and list_symbols (symbol list) by scoping to a single instrument and to level data.

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 phrase 'for one instrument' establishes clear context for when to use this tool, and 'Research/education only' adds a usage restriction. However, it does not explicitly mention alternatives (e.g., 'for a list of symbols, use list_symbols') or state when NOT to use this tool. So it has clear context but no explicit exclusions.

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