MartinLoop — Stop Runaway Loops, Bad Code & Token Waste

martin_estimate

Read-onlyIdempotent

Estimate cost, route, and pre-work burn for a coding task before execution, with optional budget caps and file scope. Use in preflight to prevent runaway spend and over-budget work.

Instructions

Read-only cost, route, and pre-work burn estimate for a software objective. Use before planning/preflight when a change may spend agent time or exceed budget. Do not use for casual questions or as permission to execute. Next: call martin_plan if the estimate is acceptable, or ask for consent if budget/risk is high.

Input Schema

TableJSON Schema

Name	Required	Description
`engine`	No	Which agent CLI would be used. Defaults to claude.
`budgetUsd`	No	Budget ceiling for estimation. Defaults to 5.
`fileScope`	No	Optional file paths to scope the estimate.
`objective`	Yes	The coding task to estimate.
`workingDirectory`	No	Optional workspace path for recording the estimate receipt against the same task root you plan to run.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`engine`	Yes
`reason`	Yes
`budgetUsd`	Yes
`objective`	Yes
`compressed`	No
`confidence`	Yes
`blockedSteps`	No
`selectedMode`	Yes
`expectedCostUsd`	Yes
`compressionSummary`	No
`recommendedBudgetUsd`	No
`expectedPreworkBurnPct`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv0.5.3Aug 19, 2026

addedInput schema / properties / workingDirectory

Added value: +{
+  "description": "Optional workspace path for recording the estimate receipt against the same task root you plan to run.",
+  "type": "string"
+}

First observedv0.3.9Jul 29, 2026

TDQS

A4.5/5.0

Behavior4/5

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

Annotations already declare readOnlyHint=true and idempotentHint=true, and the description reinforces this with 'Read-only' and 'not as permission to execute.' It adds context about producing a pre-work burn estimate and warns about budget/risk consent, going beyond the bare annotation flags. No contradictions with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences deliver purpose, usage conditions, exclusions, and next-step guidance with zero filler. The most important information—read-only estimation—is front-loaded, and every clause earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given that annotations cover read-only and idempotent behavior, the schema covers all parameters, and an output schema exists, the description fills the remaining gaps: when to use it, what it is for, and what to do next. Nothing needed for correct invocation is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the schema itself documents all parameters. The description adds general context about 'software objective' and 'budget/risk' but does not provide new meaning for individual parameters beyond the schema. Baseline 3 is appropriate; the description does not carry the parameter documentation burden.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb and resource: 'Read-only cost, route, and pre-work burn estimate for a software objective.' This clearly distinguishes the tool from planning, execution, and run-management siblings like martin_plan and martin_run. It also communicates the operative scope—estimating, not executing.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly says when to use it ('before planning/preflight when a change may spend agent time or exceed budget') and when not to ('Do not use for casual questions or as permission to execute'). It also provides a concrete next step: call martin_plan if acceptable, or ask for consent for high budget/risk. This is exemplary routing guidance.

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