cache_stream_set

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

With no annotations, the description carries the full burden. It discloses the Redis RPUSH operation, the key prefix (cachly:stream:), that chunks are stored as separate list elements, and that TTL is optional. This provides good behavioral context, though it lacks details on permissions, rate limits, or destructive side-effects.

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 sentences: first states purpose and method, second specifies storage key pattern and replay hint. No extraneous words; every part 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?

Given 4 parameters, no output schema, and no annotations, the description could be more complete. It explains the input and storage but omits what the tool returns (e.g., number of elements added, status) and doesn't address concurrency or idempotency. It is adequate but leaves gaps for an AI agent.

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 adds value by explaining the storage mechanism (RPUSH) and key pattern (cachly:stream:{key}), which are not in the schema. It also clarifies that chunks form an ordered list, reinforcing the schema description.

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 tool caches a list of string chunks via Redis RPUSH, gives an example (LLM token stream), and specifies the storage key pattern (cachly:stream:{key}). It distinguishes from sibling cache_stream_get and implies distinction from cache_set by mentioning list storage.

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 tells when to use this tool (to cache stream chunks) and hints at replay with cache_stream_get. However, it does not explicitly exclude cases like caching single values (use cache_set instead) or provide when-not-to-use conditions, leaving some ambiguity.

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