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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so the safety profile needs no restating. The description adds genuinely useful behavior beyond that: results are returned newest-first, which the annotations do not cover. It does not mention the default page size or what happens on an empty result set, leaving a small 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?

Three short, front-loaded statements with no filler, and the differentiator comes before the example. The opening repetition of the tool name 'memory_search.' is redundant overhead but negligible.

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 an output schema present, a fully documented parameter set, and safety annotations, the description only needs to supply selection guidance and result ordering, both of which it does. Missing only minor operational details such as pagination beyond limit or empty-result behavior.

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% and each of the four parameters has its own description (limit default 20/max 100, tag filter, text query, arena key). The description only echoes 'text/tag' and says nothing about limit behavior or the key parameter, so it adds little beyond the schema baseline.

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?

States a concrete verb and resource ('find notes') plus the filter dimensions ('text/tag') and result ordering ('newest first'). It explicitly distinguishes itself from memory_get (exact key) and memory_list (no query), so an agent can pick the right tool without opening a schema.

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?

A 'WHEN:' clause gives the trigger condition and names both alternatives with the property that separates them (exact key vs no query). The example 'memory_search {}' additionally signals that all parameters are optional and an empty search is valid.

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