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

With no annotations present, the description carries the full behavioral disclosure burden, and it does so strongly. It discloses the authentication/licensing requirement, refresh cadence, that the payload is identical across subscribers, the 'research, not advice' disclaimer, and that engine fields are self-described in the payload's schema block. This gives an agent accurate expectations for calling the tool.

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 longer than strictly necessary and has some promotional wording, but nearly every sentence conveys a useful operational detail: subscription, header, refresh rate, filter, payload schema self-description, and version date. It is front-loaded with the core purpose, so while it could be tightened, it remains effective.

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 read-only feed tool with zero required parameters and no output schema, the description is remarkably complete. It covers authentication, payload contents, comparison to get_full_board, filtering, refresh behavior, and how to interpret the engine fields via the payload's schema block. Nothing critically needed to invoke the tool correctly is missing.

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 only parameter, symbols, is already fully documented in the input schema with coverage at 100%. The description merely repeats 'Optional symbols[] filter' without adding any new meaning such as formatting, case sensitivity, or behavior for invalid tickers. The schema is doing the heavy lifting, so baseline 3 is appropriate.

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 states a specific resource — the engine-grade live board from coil.trade — and explicitly contrasts it with get_full_board by saying 'everything in get_full_board PLUS' engine-specific fields. It lists concrete deltas (stop/target levels, risk-reward, buy_score, conviction, lane, etc.), so an agent can clearly identify what this tool uniquely returns.

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 provides clear usage context: it requires an active Coil Live subscription, requires sending the license via X-License-Key, supports an optional symbols[] filter, and refreshes about every 5 minutes. It names get_full_board as the base alternative, but it does not explicitly state when to prefer other sibling tools or when not to use this one beyond the subscription prerequisite.

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