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

Annotations already declare readOnlyHint and openWorldHint, so the safe-read profile is covered. The description adds that only public sections are eligible and that the value is sourced from space_sections, but says nothing about auth, rate limits, or result shape (the output schema covers returns).

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?

One compact sentence that front-loads the resource and the key constraint. No filler, though the clause after the semicolon could be slightly more explicit about sourcing.

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-param read tool with an output schema, the description covers the essential call constraint. Its only gap is not distinguishing itself from the other space_* news/article tools.

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%, with a bare 'string' type and no enum, so the description carries the burden. It does so by telling the agent the value must come from space_sections, which is meaningful beyond the schema's placeholder type.

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?

Names a specific verb+resource (Space headlines) and scopes it to a single public section. It does not explicitly contrast itself with siblings like space_news or space_article, so an agent must infer the boundary, but the section-scoping is stated.

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 tells you the section value must come from space_sections, which is useful routing guidance, but it never says when to pick this tool over space_news or space_article. Usage is implied rather than explained.

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