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

Annotations cover safety (readOnly, idempotent, non-destructive), and the description adds substantial context beyond them: detection is keyword-based because the EPG lacks structured metadata, and live_status is derived with quoted evidence, with 'unknown' meaning the EPG is silent. This is exactly the kind of reliability caveat an agent needs to interpret results correctly.

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?

It is longer than average but front-loaded: the scope comes first, then the detection caveat, then the routing instruction. Each sentence carries distinct information (scope, method, live_status semantics, usage), so nothing reads as filler.

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?

An output schema exists, so return structure need not be restated. Given the moderate complexity, the description covers scope, detection methodology, live_status semantics, and when to use it — everything an agent needs to call 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 description coverage is 100%, so the schema already documents date, limit, and min_tier. The description echoes the tier concept ('major' vs 'notable') in prose but adds no format or default detail beyond what the schema states, so the baseline of 3 applies.

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 (Romanian TV broadcasts) and a clear scope (major sporting events: World Cup/Euro/Champions League, finals, knockouts), which distinguishes it from recommendation siblings like tv_recommend_today and tv_now_on_tv. The verb is slightly soft ('what actually matters') but the content type is unambiguous.

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 explicit primacy guidance — 'Use this FIRST for questions like "what's important to watch today?"' — which tells the agent when to reach for this over siblings. It does not name specific alternatives to avoid, so it stops short of a full when/when-not statement.

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