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

While annotations confirm read-only safety, the description adds critical behavioral details: output is converted to markdown format, and the hash fragment must be preserved from search results. Does not cover error handling or rate limits.

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. First sentence front-loads the action and output format; second sentence provides the critical workflow constraint. Every word 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?

Complete for a simple single-parameter read tool: explains output format (compensating for missing output schema), documents sibling relationship, and covers the hash detail. Minor gap: no mention of error handling for invalid URLs.

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?

Despite 100% schema coverage (baseline 3), description significantly enriches the 'url' parameter by specifying its provenance (must come from ref_search_documentation) and format constraints (must include #hash), adding semantic meaning beyond the schema's generic description.

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?

Specific verb ('Read') + resource ('content of a url') + output format ('as markdown'), and explicitly distinguishes from sibling by stating the URL must come from 'ref_search_documentation', establishing clear workflow boundaries.

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?

Provides clear prerequisite by stating the EXACT url (including #hash) must come from 'ref_search_documentation' results. However, it doesn't explicitly state when NOT to use the tool or mention if arbitrary URLs are acceptable.

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