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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered. The description adds that template ids are returned, but says nothing about pagination, filtering behavior, or ordering that would extend beyond the annotations. Adequate but not rich.

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?

It is short, but the structure is disjointed: the standalone fragment 'Optional for custom composition' is ambiguous about what is optional and for whom. The actual purpose statement is deferred to the final clause. Every sentence roughly earns its place, but the ordering and fragment hurt readability.

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?

With zero required parameters, an output schema present, and annotations covering safety, the main remaining need is usage routing, which the description supplies. Nothing essential for calling it correctly is missing, though a note on how category/channelId narrow results would round it out.

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 category and channelId are already documented in the schema, and the description mentions neither. The description's note that ids are returned is output-related rather than parameter-level, so it adds no parameter meaning. Baseline 3 applies.

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 ends with a concrete verb+resource statement: 'this tool lists saved templates and their ids.' It distinguishes itself from get_formatting_capabilities, which is named explicitly. The purpose is clear, though it is buried at the end of the description rather than front-loaded.

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 gives an explicit trigger ('Use this when the user wants an existing reusable Postlyra layout template') and routes the agent away to get_formatting_capabilities for supported blocks and JSON/formatting questions. No explicit when-not condition is given, but the alternative tool is named and the condition that selects it is clear.

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