list_facetsEvery distinct value of each filterable field of a catalogue (categories, rarities, crystal systems, environments, essences…) and its entry count.
| Name | Required | Description | Default |
|---|---|---|---|
| kind | Yes | Which catalogue: metal, mineral, ingredient, potion or gem. |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
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 the tool returns distinct values with entry counts, implying a non-mutating read operation, but it does not explicitly state it is read-only, mention any limits, or describe the return format in detail. This is acceptable but leaves some implicit behavior undisclosed.
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 a single, front-loaded sentence with no redundancy. Every word contributes to explaining the tool's purpose, making it an efficient and well-structured definition.
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 simplicity (one enum parameter, no output schema), the description sufficiently explains what the tool does and what it returns. It lacks details about edge cases or pagination, but for a facet-list tool this is likely sufficient. It is complete enough for an agent to call it correctly.
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 covers the single parameter 'kind' with an enum and description. The tool description adds no additional meaning beyond that, so the baseline of 3 is appropriate because the schema handles the semantics completely.
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 states the action (list) and the resource (distinct values of filterable fields of a catalogue) with examples. It is specific enough to distinguish from siblings like list_entries, which would list catalogue entries rather than facet values.
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?
No guidance is given on when to use this tool versus alternatives such as list_entries or search_encyclopedia. The description only explains what it does, not when an agent should choose it. There are no exclusions or conditions for use.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool has a clear and distinct purpose: get_entry and get_track operate on different domains (encyclopedia vs. music), list_albums/list_composers/list_entries/list_facets are distinct list operations, and search_encyclopedia/search_tracks are separate search functions. No overlap or ambiguity.
The majority of tools follow a consistent verb_noun pattern (get_entry, list_albums, search_tracks, random_entry), but audio_taxonomy and craft_rules are exceptions, not following the verb_noun structure. This is a minor deviation.
With 12 tools, the server covers both a music database and an encyclopedia/crafting reference without being overwhelming. Each tool serves a clear function, and the count is well within the typical range for a specialized server.
The tool set covers all common read operations: listing, searching, retrieving by ID, random selection, and static reference (taxonomy, rules). For a read-only reference server, this is complete, with no obvious gaps for the described domain.