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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the tool is safe. The description adds that the result includes transitions and a source URL, which is helpful but does not disclose potential quirks (e.g., handling of ambiguous times). No contradiction with annotations.

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 efficiently cover purpose and output format with no unnecessary words. Front-loaded with key verb 'Report' and specific details.

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?

No output schema, but the description explains return values (date, local time, before/after offset, source_url). Covers the main output adequately for a tool with two parameters and a nested object. Could specify whether historical or only future transitions, but still complete.

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 coverage is 100%, so schema already documents parameters. The description adds 'within a year' and mentions 'every summer/winter-time transition', providing slight extra context beyond the schema. 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 explicitly states the tool reports DST observances, next clock change, and all transitions for a year, with a source URL. It clearly differentiates from sibling tools like get_current_time by focusing on DST transitions.

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 implies usage for DST information but does not provide explicit when-to-use or when-not-to-use guidance relative to siblings like convert_time or search_cities. No alternatives are suggested.

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