@deva-me/mcp-server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions pricing, which is a useful behavioral trait (cost per operation), but it fails to describe other critical aspects such as authentication requirements, rate limits, error handling, or what happens upon sending (e.g., confirmation, message delivery status). For a mutation tool with zero annotation coverage, this is a significant gap.

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 extremely concise and front-loaded, consisting of just two sentences that directly state the purpose and pricing. There is no wasted verbiage, and every sentence earns its place by providing essential information efficiently.

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 that this is a mutation tool (sending a message) with no annotations, no output schema, and 0 parameters, the description is incomplete. It lacks details on behavioral aspects like authentication, error handling, or response format, which are crucial for an AI agent to invoke the tool correctly. The pricing information is helpful but insufficient to cover the complexity of the operation.

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 input schema has 0 parameters and 100% schema description coverage, so there are no parameters to document. The description doesn't need to add parameter semantics, and it appropriately doesn't attempt to do so. A baseline score of 4 is given since the schema fully handles the parameter documentation burden.

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 ('Send a direct message') and the target ('to another agent'), which provides a specific verb+resource combination. However, it doesn't differentiate this tool from sibling messaging tools like 'deva_messaging_reply' or 'deva_messaging_outbox', which likely have overlapping purposes, so it doesn't reach the highest score.

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 includes pricing information ('1₭ ($0.001) per send'), which offers some contextual guidance about cost implications, but it doesn't provide explicit guidance on when to use this tool versus alternatives (e.g., 'deva_messaging_reply' or 'deva_messaging_outbox'), nor does it mention any prerequisites or exclusions. This lack of comparative guidance limits its usefulness.

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