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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false, so the safety profile is covered. The description adds useful behavioral detail beyond annotations: extractive mode preserves verbatim sentences in original order, and the return value is a dict with summary plus word/char counts. No contradictions 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?

The description is compact and well-structured: a one-sentence definition, a short Args list, and a Returns line. Every part earns its place, and the most important distinction (extractive vs abstractive) is front-loaded.

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 three-parameter, scalar-input tool, the description is complete. It documents all parameters, explains the two modes, and specifies the return shape despite there being no output schema. Annotations cover safety and idempotence, so nothing essential is missing for an agent to call this tool 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 text, mode, and max_length. The description mostly restates this information, adding only marginal nuance like 'original order' for extractive mode. It meets the baseline but does not substantially extend the schema's parameter documentation.

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 opens with a specific action and resource: 'Summarize text', and immediately distinguishes the two modes (extractive vs abstractive) with concrete definitions. This clearly separates it from siblings like analyze_sentiment or extract_key_phrases, none of which perform summarization.

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 purpose statement implies use when a condensed version of text is needed, but the description never explicitly says when to prefer this tool over alternatives or when not to use it. No sibling is mentioned, so usage routing is left to inference rather than spelled out.

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