MCP Datastore Server

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

With no annotations, the description carries full burden but provides minimal behavioral insight. It mentions 'allocate IDs' which implies a write operation, but doesn't disclose if this is idempotent, has side effects, requires permissions, or how the IDs are returned (e.g., format, uniqueness). This leaves significant gaps for a mutation tool.

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 zero waste. It directly states the tool's function without unnecessary words, making it highly efficient and easy to parse.

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 complexity of a mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what 'allocate IDs' entails (e.g., returns IDs, reserves them), how it fits into workflows, or what happens after allocation, leaving the agent with insufficient context for effective use.

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 parameters (kind, count, namespace). The description adds no additional meaning beyond implying that these parameters relate to 'incomplete keys', but doesn't clarify how they interact or provide examples, meeting the baseline for high schema coverage.

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 'Allocate IDs for incomplete keys' states a purpose but is vague about what 'incomplete keys' means and doesn't specify the resource (e.g., Datastore entities). It distinguishes from siblings like datastore_createKey by focusing on ID allocation rather than key creation, but lacks specificity about the verb's exact action.

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 provided on when to use this tool versus alternatives. For example, it doesn't explain if this is for pre-allocating IDs before insertion or how it relates to siblings like datastore_insert or datastore_createKey, leaving the agent without context for selection.

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