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

Beyond the annotations (which only include idempotentHint=true and destructiveHint=false), the description discloses a critical behavioral trait: the database restarts briefly, causing a temporary connection loss. It also adds the constraint that db_ram_mb must fit the pool. This is rich, valuable context that annotations cannot convey.

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 three sentences: purpose, usage trigger, and a warning/prerequisite. Every sentence carries essential information with no redundancy. It is appropriately front-loaded with the purpose.

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?

For a mutation tool with no output schema, the description covers purpose, timing, prerequisites, parameter constraints, and side effects. It is complete enough for an agent to decide when to call it and what to expect.

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 coverage is 100%, so the baseline is 3. The description adds meaningful semantics for db_ram_mb by specifying it must be one of the sizes from get_resource_usage under db_ram.steps_mb and fit the pool, which goes beyond the schema's description. No additional insight is provided for app_id, but the schema already covers it.

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 tool's function: 'Change how much memory an app's managed database gets.' The verb 'change' plus resource 'managed database memory' is specific, and it distinguishes from siblings like resize_database_storage (which resizes storage) and resize_app (which resizes app resources).

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?

It explicitly says when to use it ('Call this when the database is slow or out of memory') and gives a prerequisite ('Only works if the app has a managed database'). It doesn't explicitly mention when not to use it or point to alternatives, but the context and sibling names provide sufficient distinction.

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