cache_get

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

With no annotations provided, the description carries full burden. It explicitly states 'Read-only — no side effects', reveals fallback behavior for org_id parameter, and describes return behavior including null for missing/expired keys. No contradictions. Could add information about error handling (invalid instance_id), but the current disclosure is thorough for a read operation.

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?

Four sentences, front-loaded with purpose and return behavior, then read-only note, then sibling alternatives. No filler or redundant information. Every sentence adds distinct value. Perfectly structured for quick parsing.

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 simple read tool with 3 parameters and no output schema, the description covers purpose, return types, key behavior, side effects, and alternatives. Missing explicit mention of error behavior (e.g., invalid instance_id) but the return of null for missing/expired handles the most common cases. Slightly short of fully comprehensive.

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 baseline is 3. The description repeats the org_id fallback logic already present in the schema description. It does not add new insights beyond what the schema already provides for key or instance_id. No compensation needed, but also no extra value.

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 verb ('Get a value from a running cache instance by key') and resource ('cache instance'). It specifies return types (string, deserialized JSON object, null for missing/expired) and distinguishes from siblings by not mentioning multiple keys until the guidelines section. This is a specific, unambiguous purpose.

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?

Explicitly names three sibling tools (cache_mget, cache_exists, semantic_search) with exact conditions for their use. Provides clear when-to-use and when-not-to-use guidance without ambiguity. No other tool in the sibling list is directly relevant to single-key retrieval, so these exclusions are sufficient.

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