search_last_results

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

With no annotations, the description carries the full burden. It discloses that it returns cached results or an empty list if not found, which is useful. However, it does not explain what 'last search' refers to, whether results are scoped to a user, or if there are any limitations like cache expiration. Some behavioral context is given, but not rich.

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 exceptionally concise and well-structured. It opens with a one-sentence purpose, then clearly separates Args and Returns. Every line is necessary and adds value, with no unnecessary repetition or filler.

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?

Given the tool's simplicity and the presence of an output schema, the description is largely complete. It covers the input, output, and the 'not found' case. The main gap is the ambiguous meaning of 'last search' and how it relates to the search_music tool, but for a straightforward cache retrieval tool, it is sufficient.

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?

The schema has no description for the query parameter (0% coverage), but the description explicitly explains: 'query: The search text used previously'. This adds clear meaning beyond the schema by indicating the query must have been used in a prior search, which is essential for correct usage.

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 clearly specifies the verb 'Get' and the resource 'cached results from the last search for a query', which precisely states what the tool does. It also distinguishes itself from sibling tools like search_music, which likely performs a new search, whereas this tool retrieves previous results.

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 implied usage is to fetch cached results instead of performing a new search, but there is no explicit 'when to use' guidance or mention of alternatives. The description does not state when this should be preferred over search_music or any other sibling, so usage is only implied.

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