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

The description explicitly says 'write chosen events to a new .ics file', which is a persistent file-writing side effect, while the annotations declare readOnlyHint=true. This directly contradicts the read-only annotation, so the behavioral transparency score must be 1. The UTC timezone note is useful but cannot offset the contradiction.

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?

Three sentences, each earning its place: purpose, input selection, and timezone behavior. The most important information is front-loaded and there is no verbose or redundant wording.

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 moderate-complexity tool with five parameters and no output schema, the description covers input mode selection, UTC handling, and the output file's intended use. However, it does not clarify what the tool returns (path, success message, or content), and the readOnlyHint contradiction leaves a material gap in the behavioral model.

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 parameter details are already well documented. The description adds high-level grouping ('either ids or a from/to window'), which is helpful, but it does not add meaning beyond what the schema already states for each field.

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 uses a specific verb ('write') with a concrete resource ('chosen events') and output format ('.ics file'), and clearly states the file's purpose ('send or import elsewhere'). It is distinct from sibling tools like events_list or ics_import by emphasizing the file-export outcome.

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 clear guidance on how to select input via 'either ids (from events_list) or a from/to window', which helps agents choose the right parameters. It does not explicitly name alternatives or when not to use the tool, but the context is strong enough to route usage.

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