SRG SSR – Tagesbriefing (Wetter + EPG)

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

Beyond the readOnlyHint and idempotentHint annotations, the description discloses meaningful runtime behavior: both data sources are fetched in parallel via 'asyncio.gather,' and a failure in one source still returns the other with a 'ToolErrorResponse' in the corresponding field. This graceful-degradation detail is genuinely useful for an agent deciding how robust the output is.

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 well structured, with the core purpose up front, then a use-case tag, important notes, and a concrete example. Every sentence adds value: the parallel-fetch note justifies the single-call approach, the degradation note sets expectations, and the example makes parameter formatting concrete.

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?

Given the output schema and annotations cover return/read-only semantics, the description provides everything needed to invoke the tool correctly: what it combines, when to use it, which business units support EPG, how failures behave, and a full parameter example. No critical operational context 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 input schema has very low description coverage and the description does not explain each parameter's role explicitly. However, the included example ('business_unit='srf', channel_id='srf-1', date='2026-04-30', latitude=47.3769, longitude=8.5417') conveys the expected shape and realistic values for all required parameters. It also mentions that EPG applies only to certain business units, which helps interpret the business_unit parameter.

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 a specific verb and resource: it 'kombiniert die 24-Stunden-Wettervorhersage von SRF Meteo mit dem EPG-Tagesprogramm eines SRG SSR TV- oder Radiosenders.' This differentiates it from the sibling weather and EPG tools by explicitly presenting it as a combined briefing in a single call.

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 gives a concrete use case ('Abendplanung, redaktionelle Tages-Briefings') and explains the benefit over two sequential roundtrips: 'ein einzelner Tool-Call genügt statt zweier sequentieller Roundtrips.' It also notes an important limitation, that EPG is only available for SRF, RTS, and RSI. However, it does not explicitly name alternative sibling tools or state when users should prefer a dedicated weather-only or EPG-only tool.

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