rail_alerts

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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint, so the safety profile is covered. The description adds that only current/active alerts are returned, which is useful freshness context, but says nothing about ordering, expiry windows, or what an alert record contains. With annotation coverage this is adequate, not rich.

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?

Two sentences, zero waste, with the resource stated first and the optional filter second. Every sentence earns its place.

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 single-optional-param read-only tool with no output schema and full annotation coverage, the description gives everything needed to invoke it correctly. The only mild gap is that the shape/scope of returned alerts is undescribed, which matters somewhat for an open-world feed.

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% — the schema only labels the property 'Line' with no description — so the description must carry the weight, and it does: it identifies the parameter as an optional line-name filter and supplies concrete example values ('Media/Wawa', 'Paoli'). It stops short of stating behavior for an unknown or mismatched line name.

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?

States a specific resource and verb: 'Current SEPTA Regional Rail service alerts and advisories.' The subject matter is clearly distinct from siblings like station_departures, next_trains, and train_schedule, though no sibling is explicitly named or excluded.

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?

Usage is implied by the word 'Current' — fetch this for active disruptions — but there is no explicit when-to-use, when-not-to-use, or routing to any alternative tool. An agent can infer the context but gets no guidance on combining it with train_status or train_schedule lookups.

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