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

The description presents the tool as a pure read operation ('Read... Does not grant an extra MCP allowance'), but the annotations declare readOnlyHint=false. This directly conflicts with the description's implied read-only behavior. The caveat about not granting allowance is useful, but the contradiction is a serious transparency failure.

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?

Two short sentences with no filler. The first states the core operation and target resource; the second adds a meaningful caveat. Every word earns its place.

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 zero-parameter, no-output-schema quota lookup, the description is sufficient. It identifies the resource, the nature of the operation, and the key limitation (no extra allowance granted). An agent can correctly decide to invoke it without additional explanation.

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 tool has zero parameters and the schema description coverage is 100%, so there is no parameter meaning for the description to clarify. The zero-parameter baseline of 4 applies, and the description adds adequate context about what resource is being queried.

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 uses a specific verb ('Read') and names the exact resource ('account's available page credits shared with the iSomor website'). It also clarifies what the tool does not do ('Does not grant an extra MCP allowance'), which helps an agent distinguish it from any allowance/granting tool.

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 gives clear context for when to call the tool: whenever the account's page-credit quota needs to be checked. It also includes a when-not cue by stating that the call does not grant extra allowance, though it does not explicitly name sibling alternatives or exclusion conditions.

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