@deva-me/mcp-server

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

With no annotations provided, the description carries the full burden. It discloses the pricing behavior ('1₭ per write'), which is valuable context not in the schema. However, it lacks other critical behavioral traits: it doesn't specify if this overwrites existing keys, requires authentication, has rate limits, or what happens on success/failure. The description adds some value but leaves significant gaps.

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 very concise with two sentences, front-loading the core purpose and following with pricing. There's no wasted text, but it could be slightly more structured by separating usage notes. Overall, it's efficient and to the point.

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 complexity (simple write operation), no annotations, no output schema, and 100% schema coverage, the description is minimally adequate. It covers the basic purpose and pricing, but for a mutation tool with no annotations, it should ideally include more behavioral context like overwrite behavior or error handling to be fully complete.

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%, so the schema already documents both parameters ('key' and 'value') adequately. The description doesn't add any meaningful semantic details beyond what's in the schema, such as key constraints or value formatting examples. Baseline 3 is appropriate when 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 clearly states the action ('Set a KV value') and resource ('for a key'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'deva_storage_kv_get' or 'deva_storage_kv_delete', which would require mentioning it's a write operation versus read or delete operations.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'deva_storage_kv_get' for reading or 'deva_storage_kv_delete' for deletion, nor does it specify prerequisites such as authentication or key existence. The pricing information hints at cost considerations but doesn't frame it as usage guidance.

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