read_memory_index

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

With no annotations provided, the description carries the behavioral burden. It discloses output scope ('just the section headings' plus a 'short tip') and a performance trait ('cheap scan'), but it does not explicitly state read-only semantics, missing-file behavior, or error handling.

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 definition is two sentences, front-loaded with what the tool returns and then the recommended follow-up. Every sentence adds useful routing or scoping information with no filler.

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 read tool with an output schema, the description gives enough context to call it correctly: what it returns, why it is cheap, and when to use the expansion sibling. Missing-file edge behavior is a minor omission but not necessary for correct invocation.

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, so the schema baseline is 4. The description appropriately adds no parameter guidance because there is nothing to configure.

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 states a specific verb and resource: 'Returns just the section headings from `.ai/memory.md` plus a short tip.' It clearly distinguishes this index scan from `read_memory_section` and from the broader `read_memory` sibling by emphasizing that it returns only headings.

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 to use this for an 'initial cheap scan' and then call `read_memory_section(name)` to expand only the needed section. This gives both the condition for using this tool and the named alternative for follow-up.

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