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

Annotations already declare readOnlyHint=true, and the description adds meaningful behavioral details beyond that: staleness statistics, maximum age of three days, not real-time, the presence of stale/stale_days/built_from_brief_date fields, and HTTP 400 refusal for unsupported inputs. This gives the agent a clear model of tool behavior.

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 compact and information-dense, with key facts front-loaded. The repetition of 'Free' at the beginning and middle is unnecessary, but overall every other sentence contributes useful information about content, freshness, fields, and limitations.

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?

Even without an output schema, the description explains what the payload contains, names the staleness fields, describes freshness bounds, and covers error behavior for unsupported inputs. For a zero-parameter read-only tool, this is sufficient for an agent to invoke it correctly and interpret the result.

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 schema is empty with 100% coverage, but the description still adds value by explicitly stating that portfolio, position, and risk-profile inputs are not accepted and will cause HTTP 400. This prevents the agent from attempting invalid arguments and reinforces the no-parameter contract.

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 identifies the tool as returning the whole current board of coin rows from tracked crypto YouTube videos, including stance, call, and dated specifics. It is specific about the resource and content, but it does not explicitly differentiate itself from the sibling board_snapshot, which may overlap.

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: this is a free, read-only view of the latest board, not real-time, with possible staleness. It also warns that portfolio/position/risk-profile inputs are rejected. It does not explicitly name alternatives or state when-not-to-use versus siblings, but the context is strong enough for safe selection.

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