summarize_session

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

With no annotations, the description carries the full burden and does well: it discloses that three persisted artifacts are created/updated, that an ANTHROPIC_API_KEY enables LLM compaction, and that a deterministic fallback exists without it. It omits whether repeated calls are idempotent or how the writes can be undone.

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 short sentences, front-loaded with the action and its outputs, followed by the trigger condition and the auth/fallback caveat. Every sentence contributes distinct information with no padding.

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 mutation tool with no annotations and no output schema, the description covers side effects, timing, and the auth-dependent execution path well. It does not describe what the agent gets back on success or failure, which is the remaining gap.

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?

Only one optional parameter at 100% schema description coverage, so the schema already defines it fully. The description adds no format, length, or content guidance for session_summary beyond noting context comes from 'saved context,' so the 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?

States a specific verb+resource ('Compact and persist session memory') and then enumerates the three concrete artifacts it produces (session summary, branch summary, project overview), which clearly distinguishes it from save_context/get_context/get_status.

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 says 'Call at end of session,' giving a clear usage trigger. It does not name a when-not condition or point at an alternative sibling for related memory operations, so it stops short of full routing guidance.

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