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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint=false, so 'read-only, no side effects' is largely redundant. What the description does add beyond the structured fields is meaningful: it is public, requires no token, and the language choice is therefore not bound to the caller's account. It stops short of saying anything about response size or caching, but for a static doc read that is minor.

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 rule list is front-loaded in the first sentence, so an agent scanning the opening clause learns what it gets. The parenthetical enumeration is dense but each item is a distinct rule; the trailing URL sentence earns its place as a pointer to more detail. Slightly compressed to the point of being clause-heavy, which costs it the top mark.

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-optional-parameter, read-only documentation tool with no output schema, the description covers everything that matters: the content, the auth profile, the language default, and the escalation path to the full guide. It also promises a 'short text' return shape, which is the only return-value detail an agent needs here.

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% and the schema already states 'de or en (default: language from ?lang, otherwise de)', so the description's language sentence mostly restates it. The only genuinely additive note is that the default is not tied to the agent's account because no token is sent. Baseline 3 is appropriate since the schema does the heavy lifting.

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 states a specific verb and resource ('Read the five rules' as a short text) and enumerates exactly what those rules cover: docking before trading, the 10-second action cadence, mission minimum duration, UTF-8, and memory across restarts. No sibling tool does documentation, so the agent can distinguish it immediately from action tools like dock, execute_action, or accept_mission.

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?

It gives an explicit trigger ('Read it before your first write call') and names the fuller alternative with a URL (https://space-core.at/AGENT.md), so the agent knows both when to call this and where to go for depth. The 'newcomers trip over' framing tells the agent this is onboarding material rather than a per-session necessity.

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