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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the bar is lower. The description still adds real behavioral context: what the record contains (normative content + Pattern guidance) and the non-obvious trait that a display_id can map to multiple subgoals because underlined variants share display_ids. It does not describe the shape of a multi-resolution result, which keeps it from a 5.

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 tight sentences with zero filler: the lookup key comes first, then the returned content, then the ambiguity caveat. Every clause carries information an agent needs.

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?

With no output schema, the description correctly steps in to say what is returned (framework normative content + Pattern layer guidance), and annotations cover the read-only nature. The remaining gaps are the unexplained `include_pattern` toggle and what an ambiguous display_id resolution actually returns, which is a moderate but not fatal omission.

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%, so the description must carry the parameter burden. It handles `id` well, giving both accepted formats and examples plus the ambiguity caveat, but `include_pattern` (default true) is never mentioned, leaving one of the two parameters undocumented everywhere. Partial compensation, not full.

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?

States a specific verb and resource ("Retrieve one subgoal") and defines the payload precisely as framework normative content plus Pattern layer guidance. The singular "one" contrasts implicitly with the sibling list_requirements, and the two example ID formats make the input model unambiguous. An agent can distinguish this from search_patterns or list_requirements without opening a schema.

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?

Usage is implied by accepting either a pattern_id or a display_id, and it appropriately warns that a display_id may resolve to multiple subgoals. However, it never states when to reach for this tool versus list_requirements, search_patterns, or resolve_id, nor what to do when the display_id is ambiguous. Adequate context, but no explicit when/when-not routing.

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